/* ==================================================================

    FILE: "/home/joze/src/tclreadline/tclreadline.c"
    LAST MODIFICATION: "Fri Sep 10 02:57:55 1999 (joze)"
    LAST MODIFICATION: "Mon Sep 13 02:21:35 1999 (joze)"
    (C) 1998, 1999 by Johannes Zellner, <johannes@zellner.org>
    $Id$
    ---

    tclreadline -- gnu readline for tcl
    Copyright (C) 1999  Johannes Zellner

     * default is " \t\n\"\\'`@$><=;|&{("
     * removed "(" <-- arrays
     * removed "{" <-- `${' variables 
     * removed "<" <-- completion lists with < ... >
     * added "[]"
     * added "}"
     */
    /* 11.Sep rl_basic_word_break_characters = " \t\n\"\\@$}=;|&[]"; */
    /* besser (11. Sept) 2. (removed \") */
    /* rl_basic_word_break_characters = " \t\n\\@$}=;|&[]"; */
    /* besser (11. Sept) 3. (removed }) */
    rl_basic_word_break_characters = " \t\n\"\\@$}>=;|&[]";
    rl_basic_word_break_characters = " \t\n\\@$=;|&[]";
    // rl_basic_quote_characters = "\"{"; // XXX ??? XXX
    // rl_completer_quote_characters = "\"";
    /*
    rl_filename_quote_characters
    = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";

    rl_filename_quoting_function

char**
TclReadlineCompletion(char* text, int start, int end)
{
    char** matches = (char**) NULL;
    int status;
    // rl_attempted_completion_over = 0;
    rl_completion_append_character = ' '; /* reset, just in case ... */

#if 0
    fprintf(stderr, "DEBUG> TclReadlineCompletion: text=|%s|\n", text);
    fprintf(stderr, "DEBUG> TclReadlineCompletion: start=|%d|\n", start);
    fprintf(stderr, "DEBUG> TclReadlineCompletion: end=|%d|\n", end);
#endif

                    return (char**) NULL;
                }
                /*
                fprintf (stderr, "(TclReadlineCompletion) len[%s]=%d\n",
                    matches[i], strlen(matches[i]));
                */
            }

            /**
             * this is a special one:
             * if the script returns exactly two arguments
             * and the second argument is the empty string,
             * the rl_completion_append_character is set
             * temporaryly to NULL.
             */
            if (2 == objc && !strlen(matches[1])) {
                i--;
                FREE(matches[1]);
                rl_completion_append_character = '\0';
            }

            matches[i] = (char*) NULL; /* terminate */
        }
        Tcl_ResetResult(tclrl_interp); /* clear result space */
    }

    if (!matches && tclrl_use_builtin_completer) {
        matches = completion_matches(text, TclReadline0generator);

#!/usr/locanl/bin/tclsh
# FILE: "/home/joze/src/tclreadline/tclreadlineCompleter.tcl"
# LAST MODIFICATION: "Fri Sep 10 03:06:31 1999 (joze)"
# LAST MODIFICATION: "Mon Sep 13 02:21:21 1999 (joze)"
# (C) 1998, 1999 by Johannes Zellner, <johannes@zellner.org>
# $Id$
# ---
#
# tclreadline -- gnu readline for tcl
# Copyright (C) 1999  Johannes Zellner
#

# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
#
# johannes@zellner.org
# http://www.zellner.org/tclreadline/
#
# ================================================================== 

# done:
#

# - after
# - append
# - array
# - bgerror
# - binary
# - break
# - catch
# - cd
# - clock
# - close
# - concat
# - continue
# - (ddd is only on M$)
# - encoding
# - eof
# - error
# - eval
# - exec
# - exit
# - expr
# - fblocked
# - fconfigure
# - fcopy
# - file
# - fileevent
# - flush
# - for # TODO
# TODO:
# - foreach # TODO
# - format # TODO
# - gets
#
#     - tcltest is missing
# - glob
# - global
# - if # TODO
# - incr
# - index
# - info
# - interp
# - join
# - lappend
#
#     - last try: as for widgets
# - llength
# - linsert
# - list
# - load
# - lrange
# - lreplace
# - lsearch
# - lsort
# - history
# - load
# - namespace
# - open
# - package
# - pkg_mkIndex
# - proc
# - puts
# - pwd
# - pid
# - read
# - regexp
# - (registry is only on M$)
# - regsub
# - rename
# - (resource is on mac only)
# - return
# - scan # TODO
# - seek
# - socket
# - source
# - split # TODO
# - string
# - subst
# - switch
# - tell
# - time # TODO ??
# - trace
# - set
# - unknown
# - unset
# - update
# - uplevel
# - upvar
# - variable
# - vwait
# - while # TODO
# 
#



namespace eval tclreadline {

namespace export \
TryFromList CompleteFromList DisplayHints Rehash \
PreviousWord CommandCompletion RemoveUsedOptions \
HostList ChannelId InChannelId OutChannelId \
Lindex Llength CompleteBoolean

#**
# TryFromList will return an empty string, if
# the text typed so far does not match any of the
# elements in list. This might be used to allow
# subsequent filename completion by the builtin
# completer.
#
proc TryFromList {text lst} {
proc TryFromList {text lst {allow ""}} {

    # puts stderr "(CompleteFromList) \ntext=|$text|"
    # puts stderr "(CompleteFromList) lst=|$lst|"
    set pre [GetQuotedPrefix ${text}]
    set matches [MatchesFromList $text $lst]
    set matches [MatchesFromList $text $lst $allow]

    # puts stderr "(CompleteFromList) matches=|$matches|"
    if {1 == [llength $matches]} { ; # unique match
        # puts stderr \nunique=$matches\n
        # puts stderr "\n|${pre}${matches}[Right ${pre}]|\n"
        set null [string index $matches 0]
        if {"<" == $null || "?" == $null} {
            return [string trim "[list $text] $lst"]
        } else {
        return [string trim ${pre}${matches}[Right ${pre}]]
            return [string trim ${pre}${matches}[Right ${pre}]]
        }
    } elseif {"" != ${matches}} {
        # puts stderr \nmore=$matches\n
        set longest [CompleteLongest ${matches}]
        # puts stderr longest=|$longest|
        if {"" == $longest} {
            return [string trim "[list $text] ${matches}"]
        } else {
            return [string trim "${pre}${longest} ${matches}"]
        }
    } else {
        return ""; # nothing to complete
    }
}

#**
# CompleteFromList will never return an empty string.
# completes, if a completion can be done, or ring
# the bell if not.
#
proc CompleteFromList {text lst} {
    set result [TryFromList ${text} ${lst}]
    if {![llength ${result}]} {
        Alert
        # return [string trim [list ${text}] ${lst}"]
        if {[llength ${lst}]} {
        return [string trim "${text} ${lst}"]
            return [string trim "${text} ${lst}"]
        } else {
            return [string trim [list ${text} {}]]
        }
    } else {
        return ${result}
    }
}

#**
proc MenuFromList {text lst} {
    return [CompleteFromList $text $lst]
# CompleteBoolean does a CompleteFromList
# with a list of all valid boolean values.
#
proc CompleteBoolean {text} {
    return [CompleteFromList $text {yes no true false 1 0}]
}
# ???????

#**
# build a list of all executables which can be
# found in $env(PATH). This is (naturally) a bit
# slow, and should not called frequently. Instead
# it is a good idea to check if the variable
# `executables' exists and then just use it's
# content instead of calling Rehash.
# (see complete(exec)).
# 
proc Rehash {} {
# proc MenuFromList {text lst} {
#     if {![llength ${text}]} {
#         return [string trim "{} ${lst}"]
#     } else {
#         return [TryFromList ${text} ${lst}]
#     }
# }

    global env
    variable executables

    if {![info exists env] || ![array exists env]} {
        return
    }
    if {![info exists env(PATH)]} {
        return
    }

    set executables 0
    foreach dir [split $env(PATH) :] {
        if {[catch [list set files [glob -nocomplain ${dir}/*]]]} { continue }
        foreach file $files {
            if {[file executable $file]} {
                lappend executables [file tail $file]
            }
        }
    }
}

#**
# build a list hosts from the /etc/hosts file.
# this is only done once. This is sort of a
# dirty hack, /etc/hosts is hardcoded ...
# 
proc HostList {} {
    # read the host table only once.

    #
    variable hosts
    if {![info exists hosts]} {
        catch {
            set id [open /etc/hosts r]
            set hosts ""
            if {0 != ${id}} {
                while {-1 != [gets ${id} line]} {
                    regsub {#.*} ${line} {} line
                    if {[llength ${line}] >= 2} {
                        lappend hosts [lindex ${line} 1]
                    }
                }
                close $id
            } 
        }
    }
    return $hosts
}

#**
# never return an empty string, never complete.
# This is useful for showing options lists for example.
#
proc DisplayHints {lst} {
    return [string trim "{} ${lst}"]
}

#**
# find (partial) matches for `text' in `lst'.
# Ring the bell and return the whole list, if
# the user tries to complete ?..? options or
# find (partial) matches for `text' in `lst'. Ring
# the bell and return the whole list, if the user
# tries to complete ?..? options or <..> hints.
# <..> hints.
#
# MatchesFromList returns a list which is not suitable
# for passing to the readline completer. Thus,
# MatchesFromList should not be called directly but
# from formatting routines as TryFromList.
#
proc MatchesFromList {text lst} {
proc MatchesFromList {text lst {allow ""}} {
    set result ""
    set text [StripPrefix $text]
    set null [string index $text 0]
    foreach char {< ?} {
    if {"<" == $null || "?" == $null} {
        Alert
        return $lst
        if {$char == $null && -1 == [string first $char $allow]} {
            Alert
            return $lst
        }
    }
    # puts stderr "(MatchesFromList) text=$text"
    # puts stderr "(MatchesFromList) lst=$lst"
    foreach word $lst {
        if {[string match ${text}* ${word}]} {
            lappend result ${word}
        }

    return ${expr_pos}
}

proc RemoveUsedOptions {line opts {terminate {}}} {
    if {[llength ${terminate}]} {
        if {[regexp -- ${terminate} ${line}]} {
            return ""
            # return ${terminate}
        }
    }
    set new ""
    foreach word ${opts} {
        if {![regexp -- ${word} ${line}]} {
        if {-1 == [string first ${word} ${line}]} {
            lappend new ${word}
        }
    }
    return [string trim ${new}]
}

proc Alert {} {
    puts -nonewline \a
    flush stdout
}


#**
# get the longest common completion
# e.g. str == {tcl_version tclreadline_version tclreadline_library}
# --> [CompleteLongest ${str}] == "tcl"
#
proc CompleteLongest {str} {
    # puts stderr str=$str
    set match0 [lindex ${str} 0]

    if {1 < [llength $value] && "" == $right} {
        return [list \"${value}\"]
    } else {
        return [list ${left}${value}${right}]
    }
}

# the following two channel proc's make use of
# the brandnew (Sep 99) `file channels' command
# but have some fallback behaviour for older
# tcl version.
#
proc InChannelId {text} {
    # return [ChannelId ${text} inChannel {stdin}]
    return [ChannelId ${text} inChannel]
proc InChannelId {text {switches ""}} {
    if [catch {set chs [file channels]}] {
        set chs {stdin}
    }
    set result ""
    foreach ch $chs {
        if {![catch {fileevent $ch readable}]} {
            lappend result $ch
        }
    }
    return [ChannelId ${text} <inChannel> $result $switches]
}

proc OutChannelId {text} {
    # return [ChannelId ${text} outChannel {stdout stderr}]
    return [ChannelId ${text} outChannel]
proc OutChannelId {text {switches ""}} {
    if [catch {set chs [file channels]}] {
        set chs {stdout stderr}
    }
    set result ""
    foreach ch $chs {
        if {![catch {fileevent $ch writable}]} {
            lappend result $ch
        }
    }
    return [ChannelId ${text} <outChannel> $result $switches]
}

proc ChannelId {text {descript channelId} {chs ""}} {
proc ChannelId {text {descript <channelId>} {chs ""} {switches ""}} {
    if {"" == ${chs}} {
        # the `file channels' command is present
        # only in pretty new versions.
        #
        if [catch {set chs [file channels]}] {
            set chs {stdin stdout stderr}
        }
    }
    if {[llength [set channel [MatchesFromList ${text} ${chs}]]]} {
    if {[llength [set channel [TryFromList ${text} "${chs} ${switches}"]]]} {
        return ${channel}
    } else {
        return [DisplayHints ${descript}]
        return [DisplayHints [string trim "${descript} ${switches}"]]
    }
}

proc QuoteQuotes {line} {
    regsub -all -- \" $line {\"} line
    regsub -all -- \{ $line {\{} line; # \}\} (keep the editor happy)
    return $line

#     return [llength $pre_text]
# 
}

proc Right {left} {
    # puts left=$left
    if {"\"" == $left} {
        return {\"}
        return "\""
    } elseif {"\\\"" == $left} {
        return "\\\""
    } elseif {"\{" == $left} {
        return "\}"
    } elseif {"\\\{" == $left} {
        return "\\\}"
    }

    set pos 0
    while {-1 != [set pos [string first $char $line $pos]]} {
        incr pos
        incr found
    }
    return $found
}

#**
# make a proper tcl list from an icomplete
# string, that is: remove the junk. This is
# complementary to `IncompleteListRemainder'.
# e.g.:
#       for {set i 1} "
#  -->  for {set i 1}
#
proc ProperList {line} {
    set last [expr [string length $line] - 1]
    for {set i $last} {$i >= 0} {incr i -1} {
        if {![catch {llength [string range $line 0 $i]}]} {
            break
        }
    }
    return [string range $line 0 $i]
}

#**
# return the last part of a line which
# prevents the line from beeing a list.
# This is complementary to `ProperList'.
#
proc IncompleteListRemainder {line} {
    set last [expr [string length $line] - 1]
    for {set i $last} {$i >= 0} {incr i -1} {
        if {![catch {llength [string range $line 0 $i]}]} {
            break
        }
    }
    incr i
    return [string range $line $i end]
}

#**
# save `lindex'. works also for non-complete lines
# with opening parentheses or quotes.
# usage as `lindex'.
# Eventually returns the Rest of an incomplete line,
# if the index is `end' or == [Llength $line].
#
proc Lindex {line pos} {
    if {[catch [list set sub [lindex $line $pos]]]} {
        set diff [expr [CountChar $line \{] - [CountChar $line \}]]
        # puts stderr diff=$diff
        if {"end" == $pos || [Llength $line] == $pos} {
            return [IncompleteListRemainder $line]
        for {set i 0} {$i < $diff} {incr i} { ; # \{ keep the editor happy
            append line \}
        }
        set line [ProperList $line]
        # puts stderr line=$line
        # puts stderr \nproper_line=|$proper_line|
        if {!$diff || [catch [list set sub [lindex $line $pos]]]} {
            if {[expr [CountChar $line \"] % 2]} { append line \" }
        }
        if {[catch [list set sub [lindex $line $pos]]]} { return {} }
    }
    return $sub
}

#**
# save `llength' (see above).
#
proc Llength {line} {
    set diff 0
    if {[catch [list set len [llength $line]]]} {
        set diff [expr [CountChar $line \{] - [CountChar $line \}]]
        # puts stderr diff=$diff
        for {set i 0} {$i < $diff} {incr i} { ; # \{ keep the editor happy
            append line \}
        set line [ProperList $line]
        }
        if {$diff < 0} {
            set diff 0
        }
        # puts stderr line=$line
        if {!$diff || [catch [list set len [llength $line]]]} {
            incr diff
            if {[expr [CountChar $line \"] % 2]} { append line \" }
        }
        if {[catch [list set len [llength $line]]]} { return {} }
    }
    # puts stderr \nline=$line
    return [expr $len - $diff]
    return $len
}

proc StripPrefix {text} {
    # puts "(StripPrefix) text=|$text|"
    set null [string index $text 0]
    if {"\"" == $null || "\{" == $null} {
        return [string range $text 1 end]
    } else {
        return $text
    }
}

proc ListCompletion {text {level -1}} {
    # TODO
    return ""
    # return [VarCompletion ${text} ${level}]
}

proc VarCompletion {text {level -1}} {
    if {-1 == ${level}} {
        set level [info level]
    } else {
        incr level
    }
    set pre [GetQuotedPrefix ${text}]

        }
        set namespaces ${new}
        unset new
    }
    set matches \
    [string trim "[uplevel ${level} info vars ${var}*] ${namespaces}"]
    if {1 == [llength $matches]} { ; # unique match

        # check if this unique match is an
        # array name, (whith no "(" yet).
        #
        if {[uplevel ${level} array exists $matches]} {
            return [VarCompletion ${matches}( ${level}]; # recursion
        } else {
            return ${pre}${matches}[Right ${pre}]
        }
    } elseif {"" != $matches} { ; # more than one match
        #puts stderr "(VarComletion) matches=|$matches|"
        #puts stderr "(VarComletion) text=|$text|"
# 
#         set common [CompleteLongest ${matches}]
#         if {"" == ${common}} {
#             return [Format ${matches} ${text}]
#         } else {
#             return [string trim "${pre}${common} ${matches}"]
#         }
# 
          return [CompleteFromList ${text} ${matches}]
          return [CompleteFromList ${text} ${matches}]
    } else {
        return ""; # nothing to complete
    }
}

proc CompleteControlStatement {text start end line pos mod pre new_line} {
    set pre [GetQuotedPrefix ${pre}]
    set cmd [Lindex $new_line 0]
    set diff [expr \
    [string length $line] - [string length $new_line]]
    if {$diff == [expr $start + 1]} {
        set mod1 $mod
    } else {
        set mod1 $text
        set pre ""
    }
    set new_end [expr $end - $diff]
    set new_start [expr $new_end - [string length $mod1]]
    # puts ""
    # puts new_start=$new_start
    # puts new_end=$new_end
    # puts new_line=$new_line
    # puts mod1=$mod1
    if {$new_start < 0} {
        return ""; # when does this occur?
    }
    # puts stderr ""
    # puts stderr start=|$start|
    # puts stderr end=|$end|
    # puts stderr mod=|$mod|
    # puts stderr new_start=|$new_start|
    # puts stderr new_end=|$new_end|
    # puts stderr new_line=|$new_line|
    # puts stderr ""
    set res [ScriptCompleter $mod1 $new_start $new_end $new_line]
    # puts stderr \n\${pre}\${res}=|${pre}${res}|
    if {[string length [Lindex ${res} 0]]} {
        return ${pre}${res}
    } else {
        return ${res}
    }
    return ""
}

proc BraceOrControlStatement {text start end line pos mod} {
    if {![string length [Lindex $line $pos]]} {
        return [list \{ {}]; # \}
    } else {
        set new_line [string trim [IncompleteListRemainder $line]]
        if {![regexp {^([\{\"])(.*)$} $new_line all pre new_line]} {
            set pre ""
        }
        return ""; # nothing to complete
        return [CompleteControlStatement $text \
        $start $end $line $pos $mod $pre $new_line]
    }
}

proc FullQualifiedMatches {qualifier matchlist} {
    set new ""
    if {"" != $qualifier && ![regexp ::$ $qualifier]} {
        append qualifier ::
    }
    foreach entry ${matchlist} {
        set full ${qualifier}::${entry}
        set full ${qualifier}${entry}
        if {"" != [namespace which ${full}]} {
            lappend new ${full}
        }
    }
    return ${new}
}

proc ProcsOnlyCompletion {cmd} {
    return [CommandCompletion ${cmd} procs]
}

proc CommandsOnlyCompletion {cmd} {
    return [CommandCompletion ${cmd} commands]
}

proc CommandCompletion {cmd {action both} {spc ::}} {
proc CommandCompletion {cmd {action both} {spc ::} {pre UNDEFINED}} {
    # puts stderr "(CommandCompletion) cmd=|$cmd|"
    # puts stderr "(CommandCompletion) action=|$action|"
    # puts stderr "(CommandCompletion) spc=|$spc|"

    # get the leading colons in `cmd'.
    if {"UNDEFINED" == $pre} {
        regexp {^:*} ${cmd} pre
    }
    # puts stderr \npre=|$pre|

    set cmd [StripPrefix ${cmd}]
    set quali [namespace qualifiers ${cmd}]
    if {[llength ${quali}]} {
        set rec [CommandCompletion [namespace tail ${cmd}] ${action} ${quali}]
        return [FullQualifiedMatches ${quali} ${rec}]
    if {[string length ${quali}]} {
        # puts stderr \nquali=|$quali|
        set matches [CommandCompletion \
        [namespace tail ${cmd}] ${action} ${spc}${quali} ${pre}]
        # puts stderr \nmatches1=|$matches|
        return $matches
    }
    # puts stderr \ncmd=|$cmd|\n
    set cmd [string trim ${cmd}]*
    # puts stderr \ncmd=|$cmd|\n
    if {"procs" != ${action}} {
        set commands [namespace eval $spc "info commands [QuoteQuotes ${cmd}]"]
        # puts stderr commands=|$commands|
        set all_commands [namespace eval $spc [list info commands ${cmd}]]
        # puts stderr all_commands=|$all_commands|
        set commands ""
        foreach command $all_commands {
            if {[namespace eval $spc [list namespace origin $command]] == \
                [namespace eval $spc [list namespace which $command]]} {
                lappend commands $command
            }
        }
    } else {
        set commands ""
    }
    if {"commands" != ${action}} {
        set procs [namespace eval $spc "info procs [QuoteQuotes ${cmd}]"]
        set all_procs [namespace eval $spc [list info procs ${cmd}]]
        # puts stderr procs=|$procs|
        set procs ""
        foreach proc $all_procs {
            if {[namespace eval $spc [list namespace origin $command]] == \
                [namespace eval $spc [list namespace which $command]]} {
                lappend procs $command
            }
        }
    } else {
        set procs ""
    }
    set matches [namespace eval $spc concat ${commands} ${procs}]
# 
#     foreach match ${matches} {
#         set full ${spc}::${match}
#         if {"" != [namespace which ${full}]} {
    set namespaces [namespace children $spc ${cmd}]
#             lappend new bla::${full}
#         }
#     }
# 

    set namespaces [namespace children $spc ${cmd}]
    if {![llength ${matches}] && 1 == [llength ${namespaces}]} {
        set namespaces [string trim ${namespaces}]
        regsub {^([^:])} $namespaces {::\1} namespaces
    #    set matches [namespace eval ${namespaces} \
        set matches [CommandCompletion {} ${action} ${namespaces} ${pre}]
    #    {concat [info commands] [info procs]}]
        if {"procs" != ${action}} {
            set n_commands [namespace eval ${namespaces} "info commands"]
        } else {
            set n_commands ""
        }
        if {"commands" != ${action}} {
            set n_procs [namespace eval ${namespaces} "info procs"]
        } else {
            set n_procs ""
        }
        # puts stderr \nmatches=|$matches|
        return $matches
    }
        set matches [string trim "${n_commands} ${n_procs}"]
        if {[llength ${matches}]} {
# 

#             foreach match ${matches} {
#                 set full ${namespaces}::${match}
    # make `namespaces' having exactly
#                 if {"" != [namespace which ${full}]} {
#                     lappend new ${namespaces}::${match}
#                 }
#             }
# 
    # the same number of colons as `cmd'.
    #
#             set matches ${new}
#             unset new
# 
            set matches [FullQualifiedMatches ${namespaces} ${matches}]
    regsub -all {^:*} $spc $pre spc

    set matches [FullQualifiedMatches ${spc} ${matches}]
            set namespaces ""
        }
        return [string trim "${matches} ${namespaces}"]
    # puts stderr \nmatches3=|$matches|
    } else {
        return [string trim "${matches} ${namespaces}"]
    }
}
    return [string trim "${matches} ${namespaces}"]
}


#**
# check, if the first argument starts with a '['
# and must be evaluated before continuing.
# NOTE: trims the `line'.
# NOTE: eventually modifies all arguments.
#       eventually modifies all arguments.
# DATE: Sep-06-1999
#
proc EventuallyEvaluateFirst {partT startT endT lineT} {
    # return; # disabled
    upvar $partT part $startT start $endT end $lineT line

    set oldlen [string length ${line}]
    set line [string trim ${line}]
    set diff [expr [string length $line] - $oldlen]
    incr start $diff
    incr end $diff

    set char [string index ${line} 0]
    if {{[} != ${char} && {$} != ${char}} {return}

    set pos 0
    while {-1 != [set idx [string first {]} ${line} ${pos}]]} {
        set cmd [string range ${line} 0 ${idx}]

# % puts $b<TAB>
# part  == $b
# start == 5
# end   == 7
# line  == "$puts $b"
#
proc ScriptCompleter {part start end line} {

    # puts stderr "(ScriptCompleter) |$part| $start $end |$line|"
    variable known_cmds

    # if the character before the cursor is a terminating
    # quote and the user wants completion, we insert a white
    # space here.
    #
    set char [string index $line [expr $end - 1]]
    if {"\}" == $char} {
        append $part " "
        return [list $part]
    }

    if {{$} == [string index $part 0]} {

        # check for a !$ history event
        #
        if {$start > 0} {
            if {{!} == [string index $line [expr $start - 1]]} {
                return ""
            }
        }
        # variable completion. Check first, if the
        # variable starts with a plain `$' or should
        # be enclosed in braces.
        #
        set var [string range $part 1 end]
# 

#         if {"\{" == [string index $part 1]} {
#             set var [string range $part 2 end]
#             set left "\{"
#         } else {
#             set left ""
#             set var [string range $part 1 end]
#         }
# 
        # check if $var is an array name, which
        # already has already a "(" somewhere inside.
        #
        if {"" != [set vc [VarCompletion $var]]} {
            if {"" == [lindex $vc 0]} {
                return "\$ [lrange ${vc} 1 end]"
            } else {
                return \$${vc}
            }
            # puts stderr vc=|$vc|
        } else {
            return ""
        }

    # SCENARIO:
    #
    # % puts bla; put<TAB> $b
    # part  == put
    # start == 10
    # end   == 13
    # line  == "puts bla; put $b"

        set new_start [lindex $sub 0]
        set new_end [expr $end - ($start - $new_start)]
        set new_line [lindex $sub 1]
        # puts stderr "(SplitLine) $new_start $new_end $new_line"
        return [ScriptCompleter $part $new_start $new_end $new_line]
    } elseif {0 == [set pos [PartPosition part start end line]]} {
        # puts stderr "(PartPosition) $part $start $end $line"
        # set matches [array names known_cmds "[string trim ${part}]*"]
        set all [CommandCompletion ${part}]
        # puts stderr "(ScriptCompleter) all=$all"
        #puts \nmatches=$matches\n
        # return [Format $all $part]
        return [TryFromList $part $all]
    } else {

        # try to use $pos further ...
        # puts stderr |$line|
        #
        if {"." == [string index [string trim ${line}] 0]} {
            set alias WIDGET
        } else {

            # the double `lindex' strips {} or quotes.
            # the subst enables variables containing
            # command names.
            #
            set alias [uplevel [info level] \
            set alias [lindex [QuoteQuotes ${line}] 0]
        }
            subst [lindex [lindex [QuoteQuotes ${line}] 0] 0]]

            # make `alias' a fully qualified name.
            # this can raise an error, if alias is
            # no valid command.
            #
            if {[catch [list set alias [namespace origin $alias]]]} {
                return ""
            }

            # strip leading ::'s.
            #
            regsub -all {^::} $alias {} alias
            set namespc [namespace qualifiers $alias]
            set alias [namespace tail $alias]
        }

        foreach cmd [list ${alias} tclreadline_complete_unknown] {
            # puts stderr ${namespc}complete(${cmd})
            if {"" != [namespace eval ::tclreadline \
            if {"" != [namespace eval ::tclreadline::${namespc} \
                [list info procs complete(${cmd})]]
            } {
                # puts found=|complete($cmd)|
                # to be more error-proof, we check here,
                # if complete($cmd) takes exactly 5 arguments.
                #
                if {6 != [set arguments [llength \
                    [namespace eval ::tclreadline \
                    [list info args complete(${cmd})]]]]
                    [namespace eval ::tclreadline::${namespc} \
                    [list info args complete($cmd)]]]]
                } {
                    error [list complete(${cmd}) takes ${arguments} \
                    arguments, but should take exactly 6.]
                }

                # remove leading quotes
                #
                set mod [StripPrefix $part]
                # puts stderr mod=$mod

                if {[catch [list set script_result \
                    [namespace eval ::tclreadline::${namespc} \
                    [complete(${cmd}) $part \
                    $start $end $line $pos $mod]] ::tclreadline::errorMsg]
                    [list complete(${cmd}) $part $start $end $line $pos $mod]]]\
                    ::tclreadline::errorMsg]
                } {
                    error "error during evaluation of `complete(${cmd})'"
                    error [list error during evaluation of `complete(${cmd})']
                }
                # puts stderr \nscript_result=|${script_result}|
                return ${script_result}
            }
            # set namespc ""; # no qualifiers for tclreadline_complete_unknown
        }
        # no specific command completer found.
        if {"" != [array names known_cmds $cmd]} {
            set current [lindex $known_cmds($cmd) $pos]
            if {"" != $current && "" == [string trim $part]} {
                return $current
            } else {
                return ""
        return ""
            }
        } else {
            return ""
        }
    }
    error "{NOTREACHED (this is probably an error)}"
}


# explicit command completers
#

    switch -- $pos {
        1 {
            return [CompleteFromList ${text} {<ms> cancel idle info}]
        }
        2 {
            switch -- $sub {
                cancel {
                    set after_info [after info]
                    if {![llength $after_info]} {
                        return [DisplayHints <script>]
                    } else {
                        return [CompleteFromList $mod "<script> [after info]"]
                    return [CompleteFromList $text "<script> [after info]"]
                    }
                }
                idle {
                    return [DisplayHints <script>]
                }
                info {
                    return [CompleteFromList $mod [after info]]
                    return [CompleteFromList $text [after info]]
                }
                default { return [DisplayHints ?script?] }
            }
        }
        default {
            switch -- $sub {
                info { return [DisplayHints {}] }

                anymore donesearch exists get names
                nextelement set size startsearch
            }
            return [CompleteFromList $text $cmds]
        }
        2 {
            set matches ""
            set vars [uplevel [info level] info vars ${mod}*]
            # set vars [uplevel [info level] info vars ${mod}*]
            #
            # better: this displays a list of array names if the
            # user inters with something which cannot be matched.
            # The matching against `text' is done by CompleteFromList.
            #
            set vars [uplevel [info level] info vars]
            foreach var ${vars} {
                if {[uplevel [info level] array exists ${var}]} {
                    lappend matches ${var}
                }
            }
            return [CompleteFromList ${text} ${matches}]
        }
        default {
        3 {
            set cmd [Lindex $line 1]
            set array_name [Lindex $line 2]
            switch -- $cmd {
                get -
                names {
                    set pattern [Lindex $line 3]
                    set matches [uplevel [info level] \
                    array names ${array_name} ${pattern}*]
                    if {![llength $matches]} {
                        return [Menu ?pattern?]
                        return [DisplayHints ?pattern?]
                    } else {
                        return [CompleteFromList ${text} ${matches}]
                    }
                }
                anymore -
                donesearch -
                nextid { return [Menu <searchId>] }
                nextelement { return [DisplayHints <searchId>] }
            }
        }
    }
    return ""
}

# proc complete(bgerror) {text start end line pos mod} {

    }
    return ""
}

# proc complete(cd) {text start end line pos mod} {
# }

proc complete(if) {text start end line pos mod} {
    # TODO: this is not good yet.
    switch -- $pos {
        1 { return [CompleteFromList $mod {\{}] }
        2 { return [TryFromList $mod {then}] }
        default {
            set prev [PreviousWord ${start} ${line}]
            switch $prev {
                then -
                else -
                elseif { return [CompleteFromList $mod {\{}] }
                default { return [TryFromList $text {then else elseif}] }
            }
        }
    }
    return ""
}

proc complete(incr) {text start end line pos mod} {
    if {1 == $pos} {
        set matches [uplevel 2 info vars "${mod}*"]
        set final ""
        # check for integers
        #
        foreach match $matches {
            if {[uplevel 2 array exists $match]} {
                continue
            }
            if {[regexp {^[0-9]+$} [uplevel 2 set $match]]} {
                lappend final $match
            }
        }
        return [Format ${final} $text]
    }
}

proc complete(clock) {text start end line pos mod} {
    set cmd [lindex $line 1]
    set cmd [Lindex $line 1]
    switch -- $pos {
        1 {
            return [TryFromList $text {clicks format scan seconds}]
            return [CompleteFromList $text {clicks format scan seconds}]
        }
        2 {
            switch -- $cmd {
                format  { return [DisplayHints clockValue] }
                scan    { return [DisplayHints dateString] }
                format  { return [DisplayHints <clockValue>] }
                scan    { return [DisplayHints <dateString>] }
                clicks  -
                seconds {}
            }
        }
        3 -
        5 {
            switch -- $cmd {
                format {
                    set subcmds [RemoveUsedOptions $line {-format -gmt}]
                    return [TryFromList $text $subcmds]
                }
                scan {
                    set subcmds [RemoveUsedOptions $line {-base -gmt}]
                    return [TryFromList $text $subcmds]
                }
                clicks  -
                seconds {}
            }
        }
        4 -
        3 {
        6 {
            set sub [Lindex $line [expr $pos - 1]]
            switch -- $cmd {
                format {
                    set sub [lindex $line 3]
                    switch -- $sub {
                    set subcmds {-fmt -gmt}
                    return [TryFromList $text $subcmds]
                }
                        -format { return [DisplayHints <string>] }
                        -gmt    { return [DisplayHints <boolean>] }
                    }
                }
                scan {
                    set sub [lindex $line 3]
                    set subcmds {-base -gmt}
                    return [TryFromList $text $subcmds]
                    switch -- $sub {
                        -base { return [DisplayHints <clockVal>] }
                        -gmt  { return [DisplayHints <boolean>] }
                    }
                }
                clicks  -
                seconds {}
            }
        }
    }
    return ""
}

proc complete(close) {text start end line pos mod} {
    switch -- $pos {
        1 { return [ChannelId $text] }
    }
    return ""
}

proc complete(concat) {text start end line pos mod} {
    return [DisplayHints ?arg?]
}

# proc complete(continue) {text start end line pos mod} {
# }

# proc complete(dde) {text start end line pos mod} {
#     We're not on windoze here ...
# }

proc complete(encoding) {text start end line pos mod} {
    set cmd [lindex $line 1]
    set cmd [Lindex $line 1]
    switch -- $pos {
        1 {
            return [TryFromList $text {convertfrom convertto names system}]
            return [CompleteFromList $text {convertfrom convertto names system}]
        }
        2 {
            switch -- $cmd {
                names {}
                convertfrom -
                convertto -
                system {
                    return [TryFromList ${text} [encoding names]]
                    return [CompleteFromList ${text} [encoding names]]
                }
            }
        }
        3 {
            switch -- $cmd {
                convertfrom { return [DisplayHints <data>] }
                convertto { return [DisplayHints <string>] }
    }
            }
        }
    }
    return ""
}

proc complete(eof) {text start end line pos mod} {
    switch -- $pos {
        1 { return [InChannelId $text] }
    }
    return ""
}

proc complete(error) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints <message>] }
        2 { return [DisplayHints ?info?] }
        3 { return [DisplayHints ?code?] }
    }
    return ""
}

proc complete(eval) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints <arg>] }
        default { return [DisplayHints ?arg?] }
    }
    return ""
}

proc complete(exec) {text start end line pos mod} {
    set redir [list | |& < <@ << > 2> >& >> 2>> >>& >@ 2>@ >&@]
    variable executables
    if {![info exists executables]} {
        Rehash
    }
    switch -- $pos {
        1 {
            return [TryFromList $text "-keepnewline -- $executables"]
        }
        default {
            set prev [PreviousWord ${start} ${line}]
            if {"-keepnewline" == $prev && 2 == $pos} {
                return [TryFromList $text "-- $executables"]
            }
            switch -exact -- $prev {
                | -
                |& { return [TryFromList $text $executables] }
                < -
                > -
                2> -
                >& -
                >> -
                2>> -
                >>& { return "" }
                <@ -
                >@ -
                2>@ -
                >&@ { return [ChannelId $text] }
                << { return [DisplayHints <value>] }
                default { return [TryFromList $text $redir "<>"] }
            }
        }
    }
    return ""
}

proc complete(exit) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints ?returnCode?] }
    }
    return ""
}

proc complete(expr) {text start end line pos mod} {
    set left $text
    set right ""
    set substitution [regexp -- {(.*)(\(.*)} $text all left right]; #-)

    set cmds {
        - + ~ !  * / % + - << >> < > <= >= == != & ^ | && || <x?y:z>
        acos    cos     hypot   sinh 
        asin    cosh    log     sqrt 
        atan    exp     log10   tan 
        atan2   floor   pow     tanh 
        ceil    fmod    sin     abs 
        double  int     rand    round 
        srand 
    }

    if {")" == [string index $text end] && -1 != [lsearch $cmds $left]} {
        return "$text "; # append a space after a closing ')'
    }

    switch -- $left {
        rand { return "rand() " }

        abs  -
        acos -
        asin -
        atan -
        ceil  -
        cos -
        cosh -
        double -
        exp -
        floor -
        int -
        log -
        log10 -
        round  -
        sin  -
        sinh  -
        sqrt  -
        srand  -
        tan  -
        tanh { return [DisplayHints <value>] }


        atan2 -
        fmod -
        hypot -
        pow { return [DisplayHints <value>,<value>] }
    }

    set completions [TryFromList $left $cmds <>]
    if {1 == [llength $completions]} {
        if {!$substitution} {
            if {"rand" == $completions} {
                return "rand() "; # rand() takes no arguments
            }
            append completions (; #-)
            return [list $completions {}]
        }
    } else {
        return $completions
    }
    return [TryFromList $text $cmds]
    return ""
}

proc complete(fblocked) {text start end line pos mod} {
    switch -- $pos {
        1 { return [InChannelId $text] }
    }
    return ""
}

proc complete(fconfigure) {text start end line pos mod} {
    set cmd [lindex $line 1]
    set cmd [Lindex $line 1]
    switch -- $pos {
        1 {
            return [ChannelId ${mod}]
            return [ChannelId ${text}]
        }
        default {
            set option [PreviousWord ${start} ${line}]
            switch -- $option {
                -blocking {
                    return [TryFromList ${text} {yes no}]
                    return [CompleteBoolean ${text}]
                }
                -buffering {
                    return [TryFromList ${text} {full line none}]
                    return [CompleteFromList ${text} {full line none}]
                }
                -buffersize {
                    if {![llength ${text}]} {
                        return [DisplayHints newSize]
                        return [DisplayHints <newSize>]
                    }
                }
                -encoding {
                    return [TryFromList ${text} [encoding names]]
                    return [CompleteFromList ${text} [encoding names]]
                }
                -eofchar {
                    return [DisplayHints {\{inChar\ outChar\}}]
                    return [DisplayHints {\{<inChar>\ <outChar>\}}]
                }
                -translation {
                    return [TryFromList ${text} {auto binary cr crlf lf}]
                    return [CompleteFromList ${text} {auto binary cr crlf lf}]
                }
                default {return [TryFromList $text {
                default {return [CompleteFromList $text \
                    [RemoveUsedOptions $line {
                    -blocking -buffering -buffersize
                    -encoding -eofchar -translation}]
                    -encoding -eofchar -translation}]]
                }
            }
        }
    }
    return ""
}

proc complete(fcopy) {text start end line pos mod} {
    switch -- $pos {
        1 {
            return [InChannelId ${mod}]
            return [InChannelId ${text}]
        }
        2 {
            return [OutChannelId ${mod}]
            return [OutChannelId ${text}]
        }
        default {
            set option [PreviousWord ${start} ${line}]
            switch -- $option {
                -size    { return [DisplayHints size] }
                -command { return [DisplayHints callback] }
                default  { return [TryFromList $text {-size -command}] }
                -size    { return [DisplayHints <size>] }
                -command { return [DisplayHints <callback>] }
                default  { return [CompleteFromList $text \
                    [RemoveUsedOptions $line {-size -command}]]
                }
            }
        }
    }
    return ""
}

proc complete(file) {text start end line pos mod} {
    switch -- $pos {
        1 {
            set cmds {
                atime attributes copy delete dirname executable exists
                extension isdirectory isfile join lstat mtime mkdir
                extension isdirectory isfile join lstat mkdir mtime
                nativename owned pathtype readable readlink rename
                rootname size split stat tail type volumes writable
            }
            return [TryFromList $text $cmds]
        }
        2 {
            set cmd [lindex $line 1]
            set cmd [Lindex $line 1]
            switch -- $cmd {
                atime -
                attributes -
                dirname -
                executable -
                exists -
                extension -

                writable {
                    return ""
                }

                copy -
                delete -
                rename {
                #    set match [MenuFromList ${mod} {-force}]
                    # return [TryFromList $text "-force [glob *]"]
                    # this is not perfect. The  `-force' and `--'
                    # options will not be displayed.
                    return ""
                }
            }
        }
    }
    return ""
}

proc complete(fileevent) {text start end line pos mod} {
    switch -- $pos {
        1 {
            return [ChannelId ${mod}]
            return [ChannelId ${text}]
        }
        2 {
            return [MenuFromList ${mod} {readable writable}]
            return [CompleteFromList ${text} {readable writable}]
        }
        3 {
            return [DisplayHints ?script?]
        }
    }
    return ""
}

proc complete(flush) {text start end line pos mod} {
    switch -- $pos {
        1 { return [ChannelId ${mod}] }
        1 { return [OutChannelId ${text}] }
    }
    return ""
}

proc complete(for) {text start end line pos mod} {
    switch -- $pos {
        1 -
        2 -
        3 -
        4 {
            return [BraceOrControlStatement $text $start $end $line $pos $mod]
        }
    }
    return ""
}

proc complete(foreach) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints <varname>] }
        2 { return [DisplayHints <list>] }
        default {
            if {[expr $pos % 2]} {
                return [DisplayHints [list ?varname? <body>]]
            } else {
                return [DisplayHints ?list?]
            }
        }
    }
    return ""
}

proc complete(format) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints <formatString>] }
        default { return [DisplayHints ?arg?] }
    }
    return ""
}

proc complete(gets) {text start end line pos mod} {
    switch -- $pos {
        1 { return [InChannelId ${mod}] }
        1 { return [InChannelId ${text}] }
        2 { return [VarCompletion ${text}]}
    }
    return ""
}

proc complete(glob) {text start end line pos mod} {
    switch -- $pos {
        1 {
            # This also is not perfect.
            # This will not display the options as hints!
            set matches [TryFromList ${mod} {-nocomplain --}]
            if {[llength [string trim ${mod}]] && [llength ${matches}]} {
            set matches [TryFromList ${text} {-nocomplain --}]
            if {[llength [string trim ${text}]] && [llength ${matches}]} {
                return ${matches}
            }
        }
    }
    return ""
}

proc complete(global) {text start end line pos mod} {
    return [VarCompletion ${text}]
}

proc complete(index) {text start end line pos mod} {
    if {1 == $pos} {
        return [VarCompletion ${text}]
    } elseif {2 == $pos && ![llength ${mod}]} {
        return <index>
proc complete(history) {text start end line pos mod} {
    switch -- $pos {
        1 {
            set cmds {add change clear event info keep nextid redo}
            return [TryFromList $text $cmds]
        }
        2 {
            set cmd [Lindex $line 1]
            switch -- $cmd {
                add { return [DisplayHints <command>] }
                change { return [DisplayHints <newValue>] }

                info -
                keep { return [DisplayHints ?count?] }

                event -
                redo { return [DisplayHints ?event?] }

                clear -
                nextid { return "" }
            }
        }
    }
    return ""
}

# --- HTTP PACKAGE ---

# create a http namespace inside
# tclreadline and import some commands.
#
namespace eval http {
    catch {
        namespace import \
        ::tclreadline::DisplayHints ::tclreadline::PreviousWord \
        ::tclreadline::CompleteFromList ::tclreadline::CommandCompletion \
        ::tclreadline::RemoveUsedOptions ::tclreadline::HostList \
        ::tclreadline::ChannelId ::tclreadline::Lindex \
        ::tclreadline::CompleteBoolean
    }
}

proc http::complete(config) {text start end line pos mod} {
    set prev [PreviousWord ${start} ${line}]
    switch -- $prev {
        -accept { return [DisplayHints <mimetypes>] }
        -proxyhost {
            return [CompleteFromList $text [HostList]]
        }
        -proxyport { return [DisplayHints <number>] }
        -proxyfilter {
            return [CompleteFromList $text [CommandCompletion $text]]
        }
        -useragent { return [DisplayHints <string>] }
        default {
            return [CompleteFromList $text [RemoveUsedOptions $line {
                -accept -proxyhost -proxyport -proxyfilter -useragent
            }]]
        }
    }
    return ""
}

proc http::complete(geturl) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints <url>] }
        default {
            set prev [PreviousWord ${start} ${line}]
            switch -- $prev {
                -blocksize { return [DisplayHints <size>] }
                -channel { return [ChannelId ${text}] }
                -command -
                -handler -
                -progress {
                    return [CompleteFromList $text [CommandCompletion $text]]
                }
                -headers { return [DisplayHints <keyvaluelist>] }
                -query { return [DisplayHints <query>] }
                -timeout { return [DisplayHints <milliseconds>] }
                -validate { return [CompleteBoolean $text] }
                default {
                    return [CompleteFromList $text [RemoveUsedOptions $line {
                        -blocksize -channel -command -handler -headers
                        -progress -query -timeout -validate
                    }]]
                }
            }
        }
    }
    return ""
}

proc http::complete(formatQuery) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints <key>] }
        2 { return [DisplayHints <value>] }
        default {
            switch [expr $pos % 2] {
                0 { return [DisplayHints ?value?] }
                1 { return [DisplayHints ?key?] }
            }
        }
    }
    return ""
}

proc http::complete(reset) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints <token>] }
        2 { return [DisplayHints ?why?] }
    }
    return ""
}

# the unknown proc handles the rest
#
proc \
http::complete(tclreadline_complete_unknown) {text start end line pos mod} {
    set cmd [Lindex $line 0]
    regsub -all {^.*::} $cmd "" cmd
    switch -- $pos {
        1 {
            switch -- $cmd {
                reset -
                wait -
                data -
                status -
                code -
                size -
                cleanup {
                    return [DisplayHints <token>]
                }
            }
        }
    }
    return ""
}

# --- END OF HTTP PACKAGE ---

proc complete(if) {text start end line pos mod} {
    # we don't offer the completion `then':
    # it's optional, more difficult to parse
    # and who uses it anyway?
    #
    switch -- $pos {
        1 -
        2 {
            return [BraceOrControlStatement $text $start $end $line $pos $mod]
        }
        default {
            set prev [PreviousWord ${start} ${line}]
            switch -- $prev {
                then -
                else -
                elseif {
                    return [BraceOrControlStatement \
                    $text $start $end $line $pos $mod]
                }
                default {
                    if {-1 == [lsearch [ProperList $line] else]} {
                        return [CompleteFromList $text {else elseif}]
                    }
                }
            }
        }
    }
    return ""
}

proc complete(incr) {text start end line pos mod} {
    switch -- $pos {
        1 {
            set matches [uplevel [info level] info vars ${mod}*]
            set integers ""
            # check for integers
            #
            foreach match $matches {
                if {[uplevel [info level] array exists $match]} {
                    continue
                }
                if {[regexp {^[0-9]+$} [uplevel [info level] set $match]]} {
                    lappend integers $match
                }
            }
            return [CompleteFromList ${text} ${integers}]
        }
        2 { return [DisplayHints ?increment?] }
    }
    return ""
}

proc complete(info) {text start end line pos mod} {
    set cmd [Lindex $line 1]
    if {1 == $pos} {
        set cmds {
            args body cmdcount commands complete default exists
            globals hostname level library loaded locals nameofexecutable
            patchlevel procs script sharedlibextension tclversion vars}
        return [TryFromList $text $cmds]
    } elseif {2 == $pos} {
    switch -- $pos {
        1 {
            set cmds {
                args body cmdcount commands complete default exists
                globals hostname level library loaded locals nameofexecutable
                patchlevel procs script sharedlibextension tclversion vars}
            return [CompleteFromList $text $cmds]
        }
        2 {
        set cmd [lindex $line 1]
        switch -- $cmd {
            args -
            body -
            default -
            procs { return [complete(proc) ${text} 0 0 ${line} 1 ${mod}] }
            complete { ; # TODO
            switch -- $cmd {
                args -
                body -
                default -
                procs { return [complete(proc) ${text} 0 0 ${line} 1 ${mod}] }
                complete { return [DisplayHints <command>] }
            }
            level { ; # TODO
                level { return [DisplayHints ?number?] }
            }
            loaded { ;# TODO
                loaded { return [DisplayHints ?interp?] }
            }
            commands -
            exists -
            globals -
            locals -
            vars {
                if {"exists" == $cmd} {
                    set do vars
                } else {
                    set do $cmd
                }
                # puts stderr [list complete(info) level = [info level]]
                return \
                [Format [uplevel 2 info ${do} "${mod}*"] $text]
                commands -
                exists -
                globals -
                locals -
                vars {
                    if {"exists" == $cmd} {
                        set do vars
                    } else {
                        set do $cmd
                    }
                    # puts stderr [list complete(info) level = [info level]]
                    return \
                    [CompleteFromList ${text} [uplevel [info level] info ${do}]]
                }
            }
        }
        3 {
            switch -- $cmd {
                default {
                    set proc [Lindex $line 2]
                    return [CompleteFromList ${text} \
                    [uplevel [info level] info args $proc]]
                }
                default {}
            }
        }
        4 {
            switch -- $cmd {
                default {
                    return [VarCompletion ${text}]
                }
                default {}
            }
        }
    }
    return ""
}

proc complete(interp) {text start end line pos mod} {
    set cmd [lindex $line 1]
    if {1 == $pos} {
        set cmds {
            alias aliases create delete eval exists expose hide hidden
            issafe invokehidden marktrusted slaves share target transfer}
        return [TryFromList $text $cmds]
    } elseif {2 == $pos} {
        switch -- $cmd {
            create {
                return [TryFromList $text {-safe -- ?path?}]
            }
    set cmd [Lindex $line 1]
    switch -- $pos {
        1 {
            set cmds {
                alias aliases create delete eval exists expose hide hidden
                invokehidden issafe marktrusted share slaves target transfer}
            return [TryFromList $text $cmds]
        }
        2 {
            switch -- $cmd {

                create {
                    set cmds [RemoveUsedOptions ${line} {-save --} {--}]
                    if {[llength $cmds]} {
                        return [CompleteFromList $text "$cmds ?path?"]
                    } else {
                        return [DisplayHints ?path?]
                    }
                }

            eval -
            exists -
            expose -
            hide -
            hidden -
            invokehidden -
            marktrusted -
            target {if {![llength ${mod}]} { return <path> }}
                eval -
                exists -
                expose -
                hide -
                hidden -
                invokehidden -
                marktrusted -
                target { return [DisplayHints [interp slaves]] }

            aliases -
            delete -
            issafe -
            slaves {if {![llength ${mod}]} { return ?path? }}
                aliases -
                delete -
                issafe -
                slaves { return [DisplayHints [interp slaves]] }

            alias -
            share -
            transfer {if {![llength ${mod}]} { return <srcPath> }}
        }
    } elseif {3 == $pos} {
        switch -- $cmd {
                alias -
                share -
                transfer { return [DisplayHints <srcPath>] }
            }
        }
        3 {
            switch -- $cmd {

            alias {if {![llength ${mod}]} { return <srcCmd> }}
                alias { return [DisplayHints <srcCmd>] }

            create {
                return [TryFromList $text {-safe -- ?path?}]
            }

            eval {if {![llength ${mod}]} { return <arg> }}
            delete {if {![llength ${mod}]} { return ?path? }}
                create {
                    set cmds [RemoveUsedOptions ${line} {-save --} {--}]
                    if {[llength $cmds]} {
                        return [CompleteFromList $text "$cmds ?path?"]
                    } else {
                        return [DisplayHints ?path?]
                    }
                }

                eval { return [DisplayHints <arg>] }
                delete { return [DisplayHints [interp slaves]] }

            expose {if {![llength ${mod}]} { return <hiddenName> }}
            hide {if {![llength ${mod}]} { return <exposedCmdName> }}
                expose { return [DisplayHints <hiddenName>] }
                hide { return [DisplayHints <exposedCmdName>] }

            invokehidden {
                return \
                [TryFromList $text {?-global? <hiddenCmdName}]
            }
                invokehidden {
                    return \
                    [CompleteFromList $text {?-global? <hiddenCmdName>}]
                }

            target {if {![llength ${mod}]} { return <alias> }}
                target { return [DisplayHints <alias>] }

            exists {}
            hidden {}
            marktrusted {}
            aliases {}
            issafe {}
            slaves {}
                exists {}
                hidden {}
                marktrusted {}
                aliases {}
                issafe {}
                slaves {}

            share -
            tranfer {return [ChannelId ${mod}]}
        }
    } elseif {4 == $pos} {
        switch -- $cmd {
                share -
                transfer {return [ChannelId ${text}]}
            }
        }
        4 {
            switch -- $cmd {

                alias { return [DisplayHints <targetPath>] }
                eval { return [DisplayHints ?arg?] }
            alias {if {![llength ${mod}]} { return <targetPath> }}

            create {
                return [TryFromList $text {-safe -- path}]
            }

            expose {if {![llength ${mod}]} { return ?exposedCmdName? }}
            hide {if {![llength ${mod}]} { return ?hiddenCmdName? }}

                invokehidden {
                    return [CompleteFromList $text {<hiddenCmdName> ?arg?}]
                }

                create {
                    set cmds [RemoveUsedOptions ${line} {-save --} {--}]
                    if {[llength $cmds]} {
                        return [CompleteFromList $text "$cmds ?path?"]
                    } else {
                        return [DisplayHints ?path?]
                    }
                }

                expose { return [DisplayHints ?exposedCmdName?] }
                hide { return [DisplayHints ?hiddenCmdName?] }

            share -
            tranfer {if {![llength ${mod}]} { return ?destPath? }}
                share -
                transfer { return [DisplayHints [interp slaves]] }
            }
        }
        5 {
            switch -- $cmd {

                alias { return [DisplayHints <targetCmd>] }
                invokehidden -
                eval { return [DisplayHints ?arg?] }

                expose { return [DisplayHints ?exposedCmdName?] }
                hide { return [DisplayHints ?hiddenCmdName?] }

                share -
                transfer { return [DisplayHints [interp slaves]] }
            }
        }
    }
    return ""
}

proc complete(join) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints <list>] }
        2 { return [DisplayHints ?joinString?] }
    }
    return ""
}
    if {1 == $pos} {
        return [VarCompletion ${text}]

proc complete(lappend) {text start end line pos mod} {
    switch -- $pos {
        1 { return [VarCompletion ${text}] }
        default { return [DisplayHints ?value?] }
    }
    return ""
}

# the following routines are described in the
# `library' man page.
# --- LIBRARY ---

proc complete(auto_execok) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints <cmd>] }
    }
    return ""
}

proc complete(auto_load) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints <cmd>] }
    }
    return ""
}

proc complete(auto_mkindex) {text start end line pos mod} {
    switch -- $pos {
        1 { return "" }
        default { return [DisplayHints ?pattern?] }
    }
    return ""
}

# proc complete(auto_reset) {text start end line pos mod} {
# }

proc complete(tcl_findLibrary) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints <basename>] }
        2 { return [DisplayHints <version>] }
        3 { return [DisplayHints <patch>] }
        4 { return [DisplayHints <initScript>] }
        5 { return [DisplayHints <enVarName>] }
        6 { return [DisplayHints <varName>] }
    }
    return ""
}

proc complete(lappend) {text start end line pos mod} {
    if {1 == $pos} {
        return [ListCompletion ${text}]
proc complete(parray) {text start end line pos mod} {
    switch -- $pos {
        1 {
            set vars [uplevel [info level] info vars]
            foreach var ${vars} {
                if {[uplevel [info level] array exists ${var}]} {
                    lappend matches ${var}
                }
            }
            return [CompleteFromList $text $matches]
        }
    }
    return ""
}

proc complete(tcl_endOfWord) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints <str>] }
        2 { return [DisplayHints <start>] }
    }
    return ""
}

proc complete(tcl_startOfNextWord) {text start end line pos mod} {
    return [complete(tcl_endOfWord) $text $start $end $line $pos $mod]
}

proc complete(tcl_startOfPreviousWord) {text start end line pos mod} {
    return [complete(tcl_endOfWord) $text $start $end $line $pos $mod]
}

proc complete(tcl_wordBreakAfter) {text start end line pos mod} {
    return [complete(tcl_endOfWord) $text $start $end $line $pos $mod]
}

proc complete(tcl_wordBreakBefore) {text start end line pos mod} {
    return [complete(tcl_endOfWord) $text $start $end $line $pos $mod]
}

# --- END OF `LIBRARY' ---

proc complete(lindex) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints <list>] }
        2 { return [DisplayHints <index>] }
    }
    return ""
}

proc complete(linsert) {text start end line pos mod} {
    if {1 == $pos} {
        return [ListCompletion ${text}]
    switch -- $pos {
        1 { return [DisplayHints <list>] }
        2 { return [DisplayHints <index>] }
        3 { return [DisplayHints <element>] }
        default { return [DisplayHints ?element?] }
    }
    return ""
}

proc complete(list) {text start end line pos mod} {
    return [DisplayHints ?arg?]
}

proc complete(llength) {text start end line pos mod} {
    if {1 == $pos} {
        return [ListCompletion ${text}]
    switch -- $pos {
        1 {
            return [DisplayHints <list>]
        }
    }
    return ""
}

proc complete(load) {text start end line pos mod} {
    if {1 == $pos} {
        return ""; # filename
    } elseif {2 == $pos && ![llength ${mod}]} {
        return "<packageName>"
    } elseif {3 == $pos && ![llength ${mod}]} {
        return "<interp>"
    switch -- $pos {
        1 {
            return ""; # filename
        }
        2 {
            if {![llength ${mod}]} {
                return [DisplayHints ?packageName?]
            }
        }
        3 {
            if {![llength ${mod}]} {
                return [DisplayHints ?interp?]
            }
        }
    }
    return ""
}

proc complete(lrange) {text start end line pos mod} {
    if {1 == $pos} {
        return [ListCompletion ${text}]
    switch -- $pos {
        1 { return [DisplayHints <list>] }
    } elseif {2 == $pos && ![llength ${mod}]} {
        return "<first>"
        2 { return [DisplayHints <first>] }
    } elseif {3 == $pos && ![llength ${mod}]} {
        return "<last>"
        3 { return [DisplayHints <last>] }
    }
    return ""
}

proc complete(lreplace) {text start end line pos mod} {
    if {1 == $pos} {
        return [ListCompletion ${text}]
    switch -- $pos {
        1 { return [DisplayHints <list>] }
    } elseif {2 == $pos && ![llength ${mod}]} {
        return "<first>"
        2 { return [DisplayHints <first>] }
    } elseif {3 == $pos && ![llength ${mod}]} {
        return "<last>"
        3 { return [DisplayHints <last>] }
    } elseif {![llength ${mod}]} {
        return "?element?"
        default { return [DisplayHints ?element?] }
    }
    return ""
}

proc complete(lsearch) {text start end line pos mod} {
    if {1 == $pos} {
        set options [MenuFromList ${mod} {
            -exact -glob -regexp <list>}]
        set matches [ListCompletion ${text}]
        return [string trim "${matches} ${options}"]
    } else {
        if {![llength ${mod}]} {
            set opt [lindex ${line} 1]
    set options {-exact -glob -regexp}
    switch -- $pos {
        1 {
            return [CompleteFromList ${text} "$options <list>"]
        }
        2 -
        3 -
        4 {
            set sub [Lindex $line 1]
            if {[llength [MenuFromList ${opt} {
                -exact -glob -regexp }]]} {
            if {-1 != [lsearch $options $sub]} {
                incr pos -1
            }
            if {1 == $pos} {
                return <list>
            switch -- $pos {
                1 { return [DisplayHints <list>] }
            } elseif {2 == $pos} {
                return <pattern>
                2 { return [DisplayHints <pattern>] }
            }
        }
    }
    return ""
}

proc complete(lsort) {text start end line pos mod} {
    set options [DisplayHints ${mod} {
    set options [RemoveUsedOptions ${line} {
        -ascii -dictionary -integer -real -command
        -increasing -decreasing -index
        -increasing -decreasing -index <list>
    }]
    set matches [ListCompletion ${text}]
    return [string trim "${matches} ${options}"]
    switch -- $pos {
        1 { return [CompleteFromList ${text} ${options}] }
}

        default {
proc complete(history) {text start end line pos mod} {
    if {1 == $pos} {
        set cmds {add change clear event info keep nextid redo}
        return [TryFromList $text $cmds]
    } elseif {2 == ${pos}} {
        set cmd [lindex $line 1]
        switch -- $cmd {
            add { if {![llength ${mod}]} { return <newValue> } }
            change { if {![llength ${mod}]} { return <newValue> } }

            switch -- [PreviousWord ${start} ${line}] {
                -command {
                    return [CompleteFromList $text [CommandCompletion $text]]
                }
            info -
            keep { if {![llength ${mod}]} { return ?count? } }

                -index { return [DisplayHints <index>] }
                default { return [CompleteFromList ${text} ${options}] }
            event -
            redo { if {![llength ${mod}]} { return ?event? } }

            }
            clear -
            nextid { return "" }
        }
    }
    return ""
}

# --- MSGCAT PACKAGE ---

# create a msgcat namespace inside
# tclreadline and import some commands.
#
namespace eval msgcat {
    catch {namespace import ::tclreadline::DisplayHints}
}

proc msgcat::complete(mc) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints <src-string>] }
    }
    return ""
}

proc msgcat::complete(mclocale) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints ?newLocale?] }
    }
    return ""
}

# proc msgcat::complete(mcpreferences) {text start end line pos mod} {
# }

proc msgcat::complete(mcload) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints <dirname>] }
    }
    return ""
}

proc msgcat::complete(mcset) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints <locale>] }
        2 { return [DisplayHints <src-string>] }
        3 { return [DisplayHints ?translate-string?] }
    }
    return ""
}

proc msgcat::complete(mcunknown) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints <locale>] }
        2 { return [DisplayHints <src-string>] }
    }
    return ""
}

# --- END OF MSGCAT PACKAGE ---

# TODO import ! -force
proc complete(namespace) {text start end line pos mod} {
    regsub {^([^:])} ${mod} {::\1} mod
    # TODO dosn't work ???
    set space_matches [namespace children :: [string trim ${mod}*]]
    # puts \nspace_matches=|${space_matches}|
    set cmd [lindex $line 1]
    if {1 == $pos} {
        set cmds {
            children code current delete eval export forget
            import inscope origin parent qualifiers tail which}
        return [TryFromList $text $cmds]
    } elseif {2 == $pos} {
        switch -- $cmd {
            children -
            delete -
            eval -
            inscope -
            forget -
            parent { return [TryFromList ${mod} $space_matches] }
            code { return "" }
            current {}
            export { return [MenuFromList ${mod} {-clear ?pattern?}] }
            import {
                return [MenuFromList ${mod} {-force $space_matches}]
            }
            origin { if {![llength ${mod}]} { return <command> } }
            qualifiers -
            tail { if {![llength ${mod}]} { return <string> } }
            which { return [MenuFromList ${mod} {
                -command -variable <name>}] }
        }
    set cmd [Lindex $line 1]
    switch -- $pos {
        1 {
            set cmds {
                children code current delete eval export forget
                import inscope origin parent qualifiers tail which}
            return [TryFromList $text $cmds]
        }
        2 {
            switch -- $cmd {
                children -
                delete -
                eval -
                inscope -
                forget -
                parent -
                qualifiers -
                tail {
                    regsub {^([^:])} ${mod} {::\1} mod; # full qual. name
                    return [TryFromList ${mod} $space_matches]
                }
                code { return [DisplayHints <script> ] }
                current {}
                export { return [CompleteFromList ${text} {-clear ?pattern?}] }
                import {
                    if {"-" != [string index ${mod} 0]} {
                        regsub {^([^:])} ${mod} {::\1} mod; # full qual. name
                    }
                    return [CompleteFromList ${mod} "-force $space_matches"]
                }
                origin { return [DisplayHints <command>] }
                # qualifiers -
                # tail { return [DisplayHints <string>] }
                which { return [CompleteFromList ${mod} {
                    -command -variable <name>}] }
            }
     #      forget { if {![llength ${mod}]} { return ?pattern? } }
    } elseif {3 == $pos && "inscope" == $cmd} {
            if {![llength ${mod}]} { return arg }
    } else {
        switch -- $cmd {
            children { if {![llength ${mod}]} { return ?pattern? } }
            delete { return [TryFromList $text $space_matches] }
            eval { if {![llength ${mod}]} { return ?arg? } }
            inscope { if {![llength ${mod}]} { return ?arg? } }
            parent {}
            code {}
            current {}
            export -
            forget -
            import { return [DisplayHints ?pattern?] }
            origin {}
            qualifiers {}
            tail {}
            which { return [MenuFromList $text {
                -command -variable <name>}] }
        }
        3 {
            switch -- $cmd {
                children -
                export -
                forget -
                import { return [DisplayHints ?pattern?] }
                delete { return [TryFromList ${mod} $space_matches] }
                eval -
                inscope { return [DisplayHints <arg>] }
                which { return [CompleteFromList ${mod} {-variable <name>}] }
            }
        }
        4 {
            switch -- $cmd {
                export -
                forget -
                import { return [DisplayHints ?pattern?] }
                delete { return [TryFromList ${mod} $space_matches] }
                eval -
                inscope { return [DisplayHints ?arg?] }
                which { return [CompleteFromList ${mod} {<name>}] }
            }
        }
    }
    return ""
}

proc complete(open) {text start end line pos mod} {
    if {![llength ${mod}]} {
        if {2 == $pos} {
            return ?access?
        # 2 { return [DisplayHints ?access?] }
    switch -- $pos {
        2 {
            set access {r r+ w w+ a a+ 
        } elseif {3 == $pos} {
            return ?permissions?
                RDONLY WRONLY RDWR APPEND CREAT EXCL NOCTTY NONBLOCK TRUNC}
            return [CompleteFromList ${text} $access]
        }
        3 { return [DisplayHints ?permissions?] }
    }
    return ""
}

proc complete(package) {text start end line pos mod} {
    set cmd [lindex $line 1]
    if {1 == $pos} {
        set cmds {
            forget ifneeded names present provide require
            unknown vcompare versions vsatisfies}
        return [TryFromList $text $cmds]
    } elseif {2 == $pos} {
        switch -- $cmd {
            forget -
            ifneeded -
            provide -
            versions { return [MenuFromList ${mod} [package names]] }
            present -
            require {
                return [MenuFromList ${mod} "-exact [package names]"] }
            names {}
            unknown { if {![llength ${mod}]} { return ?command? } }
            vcompare -
            vsatisfies { if {![llength ${mod}]} { return <version1> } }
        }
    } elseif {3 == $pos} {
        switch -- $cmd {
            forget {}
            ifneeded { if {![llength ${mod}]} { return <version> } }
            provide { if {![llength ${mod}]} { return ?version? } }
            versions {}
            present -
            require {
                set prev [PreviousWord ${start} ${line}]
    set cmd [Lindex $line 1]
    switch -- $pos {
        1 {
            set cmds {
                forget ifneeded names present provide require
                unknown vcompare versions vsatisfies}
            return [TryFromList $text $cmds]
        }
        2 {
            switch -- $cmd {
                forget -
                ifneeded -
                provide -
                versions { return [CompleteFromList ${mod} [package names]] }
                present -
                require {
                    return [CompleteFromList ${mod} "-exact [package names]"] }
                names {}
                unknown { return [DisplayHints ?command?] }
                vcompare -
                vsatisfies { return [DisplayHints <version1>] }
            }
        }
        3 {
            switch -- $cmd {
                forget {}
                ifneeded { return [DisplayHints <version>] }
                provide { return [DisplayHints ?version?] }
                versions {}
                present -
                require {
                    if {"-exact" == [PreviousWord ${start} ${line}]} {
                if {[llength [MenuFromList ${prev} -exact]]} {
                    return [MenuFromList ${mod} [package names]]
                } elseif {![llength ${mod}]} {
                    return ?version?
                }
            }
            names {}
            unknown {}
            vcompare -
            vsatisfies { if {![llength ${mod}]} { return <version2> } }
        }
    } 
                        return [CompleteFromList ${mod} [package names]]
                    } else {
                        return [DisplayHints ?version?]
                    }
                }
                names {}
                unknown {}
                vcompare -
                vsatisfies { return [DisplayHints <version2>] }
            }
        }
    }
    return ""
}

proc complete(pid) {text start end line pos mod} {
    switch -- $pos {
        1 { return [ChannelId ${text}] }
    }
}

proc complete(pkg_mkIndex) {text start end line pos mod} {
    set cmds [RemoveUsedOptions ${line} {-direct -load -verbose -- <dir>} {--}]
    set res [string trim [MenuFromList $text $cmds]]
    if {[regexp -- [PreviousWord ${start} ${line}] -load] \
    set res [string trim [TryFromList $text $cmds]]
    set prev [PreviousWord ${start} ${line}]
        && ![llength ${mod}]} {
            return <pkgPat>
    }
    if {![llength [join ${res}]]} {
        return ""
    } else {
        return ${res}
    if {"-load" == $prev} {
        return [DisplayHints <pkgPat>]
    } elseif {"--" == $prev} {
        return [TryFromList ${text} <dir>]
    }
    return ""
    return ${res}
}

proc complete(proc) {text start end line pos mod} {
    # puts known_procs=|${known_procs}|
    if {1 == $pos} {
        set known_procs [ProcsOnlyCompletion ${mod}]
    switch -- $pos {
        1 {
            set known_procs [ProcsOnlyCompletion ${text}]
        set common [CompleteLongest ${known_procs}]
        if {"" == ${common}} {
            return [Format ${known_procs} ${text}]
        } else {
            return [string trim "${common} ${known_procs}"]
            return [CompleteFromList ${text} ${known_procs}]
        }
    } elseif {2 == $pos} {
        set proc [lindex $line 1]
        if {[catch {set args [uplevel 2 info args ${proc}]}]} {
            return ""
        } else {
            return [list "\{${args}\} \{"]
        2 {
            set proc [Lindex $line 1]
            if {[catch {set args [uplevel [info level] info args ${proc}]}]} {
                return [DisplayHints <args>]
            } else {
                return [list "\{${args}\}"]
            }
        }
        3 {
            if {![string length [Lindex $line $pos]]} {
                return [list \{ {}]; # \}
            } else {
                return [DisplayHints <body>]
            }
        }
    }
    return ""
}

proc complete(puts) {text start end line pos mod} {
    if {1 == $pos} {
        return [TryFromList ${mod} "-nonewline [OutChannelId ${mod}]"]
    } elseif {2 <= $pos} {
        if {![llength ${mod}]} {
    set cmd [Lindex $line 1]
    switch -- $pos {
        1 {
            set opt [lindex ${line} 1]
            if {[llength [MenuFromList ${opt} {-nonewline}]]} {
            return [OutChannelId ${text} "-nonewline"]
                incr pos -1
            }
            if {1 == $pos} {
                return [OutChannelId ${mod}]
        }
        2 {
            switch -- $cmd {
                -nonewline { return [OutChannelId ${text}] }
            } elseif {2 == $pos} {
                return [DisplayHints <string>]
                return <string>
                default { return [DisplayHints <string>] }
            }
        }
        3 {
            switch -- $cmd {
                -nonewline { return [DisplayHints <string>] }
            }
        }
    }
    return ""
}

# proc complete(pwd) {text start end line pos mod} {
# }

proc complete(read) {text start end line pos mod} {
    set cmd [Lindex $line 1]
    if {1 == $pos} {
        return [MenuFromList ${mod} {-nonewline [InChannelId ${mod}]}]
    } elseif {2 == $pos} {
        if {![llength ${mod}]} {
    switch -- $pos {
        1 {
            return [InChannelId ${text} "-nonewline"]
        }
        2 {
            switch -- $cmd {
            set opt [lindex ${line} 1]
            if {[llength [MenuFromList ${opt} {-nonewline}]]} {
                return [InChannelId ${mod}]
                -nonewline { return [InChannelId ${text}] }
            } elseif {![llength ${mod}]} {
                return [DisplayHints <numBytes>]
                default { return [DisplayHints <numChars>] }
            }
        }
    }
    return ""
}

proc complete(regexp) {text start end line pos mod} {
    set prev [PreviousWord ${start} ${line}]
    if {[llength ${prev}] && "--" != $prev && \
    if {[llength ${prev}] && ("-" == [string index ${prev} 0] || 1 == $pos)} {
        ("-" == [string index ${prev} 0] || 1 == $pos)} {
        set cmds [RemoveUsedOptions ${line} {
            -nocase -indices -expanded -line 
            -linestop -lineanchor -about <expression> --} {--}]
        if {[llength ${cmds}]} {
            return [string trim [MenuFromList $text $cmds]]
            return [string trim [CompleteFromList $text $cmds]]
        }
    } else {
        set virtual_pos [expr ${pos} - [FirstNonOption ${line}]]
        switch -- ${virtual_pos} {
            1 { if {![llength ${mod}]} { return <string> } }
            2 { if {![llength ${mod}]} { return ?matchVar? } }
            default { if {![llength ${mod}]} { return ?subMatchVar? } }
            0 { return [DisplayHints <string>] }
            1 { return [DisplayHints ?matchVar?] }
            default { return [DisplayHints ?subMatchVar?] }
        }
    }
    return ""
}

# proc complete(regexp) {text start end line pos mod} {
#     We're not on windoze here ...
# }

proc complete(regsub) {text start end line pos mod} {
    set prev [PreviousWord ${start} ${line}]
    if {[llength ${prev}] && "--" != $prev && \
    if {[llength ${prev}] && ("-" == [string index ${prev} 0] || 1 == $pos)} {
        set cmds [RemoveUsedOptions ${line} {-all -nocase -- <expression>} {--}]
        ("-" == [string index ${prev} 0] || 1 == $pos)} {
        set cmds [RemoveUsedOptions ${line} {
        set res [string trim [MenuFromList ${mod} ${cmds}]]
        if {[llength ${res}]} {
            return ${res}
            -all -nocase --} {--}]
        if {[llength ${cmds}]} {
            return [string trim [CompleteFromList $text $cmds]]
        }
    } else {
        set virtual_pos [expr ${pos} - [FirstNonOption ${line}]]
        switch -- ${virtual_pos} {
            1 { if {![llength ${mod}]} { return <expression> } }
            2 { if {![llength ${mod}]} { return <string> } }
            3 { if {![llength ${mod}]} { return <subSpec> } }
            4 { if {![llength ${mod}]} { return <varName> } }
            0 { return [DisplayHints <expression>] }
            1 { return [DisplayHints <string>] }
            2 { return [DisplayHints <subSpec>] }
            3 { return [DisplayHints <varName>] }
        }
    }
    return ""
}

proc complete(rename) {text start end line pos mod} {
    if {1 == $pos} {
        # TODO set all [CommandCompletion ${mod}]
    switch -- $pos {
        1 {
            return [CompleteFromList $text [CommandCompletion $text]]
        return [Format $all ${mod}]
    } elseif {2 == $pos && ![llength ${mod}]} {
        return <newName>
        }
        2 {
            return [DisplayHints <newName>]
        }
    }
    return ""
}

# proc complete(resource) {text start end line pos mod} {
#     This is not a mac ...
# }

proc complete(return) {text start end line pos mod} {
    # TODO this is not perfect yet
    set cmds {-code -errorinfo -errorcode <string>}
    set res [MenuFromList [PreviousWord ${start} ${line}] ${cmds}]
    set cmds {-code -errorinfo -errorcode ?string?}
    set res [PreviousWord ${start} ${line}]
    if {1 == [llength ${res}]} {
        switch -- ${res} {
            -errorinfo { if {![llength ${mod}]} { return <info> } }
            -code -
            -errorcode {
                set codes {ok error return break continue}
                return [TryFromList ${mod} ${codes}]
    switch -- ${res} {
        -errorinfo { return [DisplayHints <info>] }
        -code -
        -errorcode {
            set codes {ok error return break continue}
            return [TryFromList ${mod} ${codes}]
        }
    }
    return [CompleteFromList ${text} [RemoveUsedOptions ${line} ${cmds}]]
}

# --- SAFE PACKAGE ---

# create a safe namespace inside
# tclreadline and import some commands.
#
namespace eval safe {
    catch {
        namespace import \
        ::tclreadline::DisplayHints ::tclreadline::PreviousWord \
        ::tclreadline::CompleteFromList ::tclreadline::CommandCompletion \
        ::tclreadline::RemoveUsedOptions ::tclreadline::HostList \
        ::tclreadline::ChannelId ::tclreadline::Lindex \
        ::tclreadline::CompleteBoolean
    }
    variable opts
    set opts {
        -accessPath -statics -noStatics -nested -nestedLoadOk -deleteHook
    }
    proc SlaveOrOpts {text start line pos slave} {
        set prev [PreviousWord ${start} ${line}]
        variable opts
        if {$pos > 1} {
            set slave ""
        }
        switch -- $prev {
            -accessPath { return [DisplayHints <directoryList>] }
            -statics { return [CompleteBoolean $text] }
            -nested { return [CompleteBoolean $text] }
            -deleteHook { return [DisplayHints <script>] }
            default {
                return [CompleteFromList ${text} \
                [RemoveUsedOptions ${line} "${opts} $slave"]]
            }
        }
    }
}
    set cmds [RemoveUsedOptions ${line} ${cmds}]
    set res [string trim [MenuFromList ${mod} ${cmds}]]
    if {[llength ${res}]} {
        return ${res}
    }

proc safe::complete(interpCreate) {text start end line pos mod} {
    return [SlaveOrOpts $text $start $line $pos ?slave?]
}

proc safe::complete(interpInit) {text start end line pos mod} {
    return [SlaveOrOpts $text $start $line $pos [interp slaves]]
}

proc safe::complete(interpConfigure) {text start end line pos mod} {
    return [SlaveOrOpts $text $start $line $pos [interp slaves]]
}

proc safe::complete(interpDelete) {text start end line pos mod} {
    return [CompleteFromList $text [interp slaves]]
}

proc safe::complete(interpAddToAccessPath) {text start end line pos mod} {
    switch -- $pos {
        1 { return [CompleteFromList $text [interp slaves]] }
    }
}

proc safe::complete(interpFindInAccessPath) {text start end line pos mod} {
    switch -- $pos {
        1 { return [CompleteFromList $text [interp slaves]] }
    }
}

proc safe::complete(setLogCmd) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints ?cmd?] }
        default { return [DisplayHints ?arg?] }
    }
}

# --- END OF SAFE PACKAGE ---

proc complete(scan) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints <string>] }
        2 { return [DisplayHints <format>] }
        default { return [VarCompletion ${text}] }
    }
    return ""
}

proc complete(seek) {text start end line pos mod} {
    if {1 == $pos} {
        return [ChannelId ${mod}]
    switch -- $pos {
        1 { return [ChannelId ${text}] }
    } elseif {2 == $pos} {
        return [TryFromList ${mod} {start current end}]
        2 { return [DisplayHints <offset>] }
        3 { return [TryFromList ${text} {start current end}] }
    }
    return ""
}

proc complete(set) {text start end line pos mod} {
    # puts stderr "\ntext=|$text| $start $end\n"
    # puts stderr \nline=|$line|\n
    # puts stderr \npos=|$pos|\n
    # puts stderr \nmod=|$mod|\n
    if {1 == $pos} {
        return [VarCompletion ${text}]
    } elseif {2 == $pos && ($text == "" || $text == "\"" || $text == "\{")} {
        set line [QuoteQuotes $line]
        if {[catch "set value [list [uplevel [info level] set [lindex $line 1]]]" msg]} {
            return ""
        } else {
            return [Quote $value ${text}]
    switch -- $pos {
        1 { return [VarCompletion ${text}] }
        2 {
            if {$text == "" || $text == "\"" || $text == "\{"} {
                set line [QuoteQuotes $line]
                if {[catch [list set value [list [uplevel [info level] \
                    set [Lindex $line 1]]]] msg]
                } {
                    return ""
                } else {
                    return [Quote $value ${text}]
                }
            }
        }
    }
    return ""
}

proc complete(socket) {text start end line pos mod} {
    set cmd [lindex ${line} 1]
    set cmd [Lindex ${line} 1]
    set prev [PreviousWord ${start} ${line}]
    if {"-server" == ${cmd}} {
        # server sockets
        #
        if {2 == $pos && ![llength ${mod}]} { return <command> }
        switch -- ${prev} {
            -myaddr { if {![llength ${mod}]} { return <addr> } }
        }
        switch -- $pos {
            2 { return [DisplayHints <command>] }
            default {
                if {"-myaddr" == $prev} {
                    return [DisplayHints <addr>]
                } else {
                    return [CompleteFromList ${mod} \
                    [RemoveUsedOptions $line {-myaddr -error -sockname <port>}]]
                }
        return [TryFromList ${mod} [concat {-error -sockname -peername}]]
            }
        }
    } else {
        # client sockets
        #
        switch -- ${prev} {
            -myaddr { if {![llength ${mod}]} { return <addr> } }
            -myport { if {![llength ${mod}]} { return <port> } }
            -myaddr { return [DisplayHints <addr>] }
            -myport { return [DisplayHints <port>] }
        }

        # read the host table only once.
        #
        variable hosts
        if {![info exists hosts] && "-server" != ${cmd}} {
            set id [open /etc/hosts r]
            set hosts ""
        set hosts [HostList]
            if {0 != ${id}} {
                while {-1 != [gets ${id} line]} {
                    regsub {#.*} ${line} {} line
                    if {[llength ${line}] >= 2} {
                        lappend hosts [lindex ${line} 1]
                    }
                }
                close $id
            } 
        }
        set cmds {-myaddr -myport -async -myaddr -error -sockname -peername}
        if {$pos <= 1} {
            lappend cmds -server
        }
        set cmds [RemoveUsedOptions $line $cmds]
        if {-1 != [lsearch $hosts $prev]} {
            return [DisplayHints <port>]
        } else {
        return [TryFromList ${mod} [concat ${cmds} ${hosts}]]
            return [CompleteFromList ${mod} [concat ${cmds} ${hosts}]]
        }
    }
    return ""
}

proc complete(source) {text start end line pos mod} {
    return ""; # force file name completion
# proc complete(source) {text start end line pos mod} {
# }

proc complete(split) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints <string>] }
        2 { return [DisplayHints ?splitChars?] }
    }
}

proc complete(string) {text start end line pos mod} {
    set cmd [lindex ${line} 1]
    set cmd [Lindex ${line} 1]
    set prev [PreviousWord ${start} ${line}]
    set cmds {
        compare first index last length match range tolower
        totitle toupper trim trimleft trimright wordend wordstart}
    if {1 == $pos} {
        return [TryFromList ${mod} ${cmds}]
    } elseif {2 == $pos} {
        switch -- $cmd {
            compare -
            first -
            last { if {![llength ${mod}]} { return <string1> } }
        bytelength compare equal first index is last length map match
        range repeat replace tolower toupper totitle trim trimleft
        trimright wordend wordstart}
    switch -- $pos {
        1 {
            return [CompleteFromList ${text} ${cmds}]
        }
        2 {
            switch -- $cmd {
                compare -
                equal {
                    return [CompleteFromList ${text} {
                        -nocase -length <string> }]
                }

                first -
                last { return [DisplayHints <string1>] }

                map { return [CompleteFromList ${text} {-nocase <charMap>]} }
                match { return [CompleteFromList ${text} {-nocase <pattern>]} }
            match { if {![llength ${mod}]} { return <pattern> } }

            index -
            length -
            range -
            tolower -
            totitle -
            toupper -
            trim -
            trimleft -
            trimright -
            wordend -
            wordstart { if {![llength ${mod}]} { return <string> } }
        }
    } elseif {3 == $pos} {
        switch -- $cmd {
            compare -
            first -
            last { if {![llength ${mod}]} { return <string2> } }

            index { if {![llength ${mod}]} { return <charIndex> } }
            length {}

            match { if {![llength ${mod}]} { return <string> } }

            range { if {![llength ${mod}]} { return <first> } }

                is {
                    return [CompleteFromList ${text} {
                        alnum alpha ascii boolean control digit double 
                        false graph integer lower print punct space 
                        true upper wordchar xdigit 
                    }]
                }

                bytelength -
                index -
                length -
                range -
                repeat -
                replace -
                tolower -
                totitle -
                toupper -
                trim -
                trimleft -
                trimright -
                wordend -
                wordstart { return [DisplayHints <string>] }
            }
        }
        3 {
            switch -- $cmd {
                compare -
                equal {
                    if {"-length" == $prev} {
                        return [DisplayHints <int>]
                    }
                    return [CompleteFromList ${text} \
                    [RemoveUsedOptions $line {-nocase -length <string>}]]
                }

                first -
                last { return [DisplayHints <string2>] }

                map {
                    if {"-nocase" == $prev} {
                        return [DisplayHints <charMap>]
                    } else {
                        return [DisplayHints <string>]
                    }
                }
                match {
                    if {"-nocase" == $prev} {
                        return [DisplayHints <pattern>]
                    } else {
                        return [DisplayHints <string>]
                    }
                }

                is {
                    return [CompleteFromList ${text} \
                    [RemoveUsedOptions $line {-strict -failindex <string>}]]
                }

                bytelength {}
                index -
                wordend -
                wordstart { return [DisplayHints <charIndex>] }
                range -
                replace { return [DisplayHints <first>] }
                repeat { return [DisplayHints <count>] }
                tolower -
                totitle -
                toupper { return [DisplayHints ?first?] }
                trim -
                trimleft -
                trimright { return [DisplayHints ?chars?] }
            }
        }
        4 {
            switch -- $cmd {
                compare -
                equal {
                    if {"-length" == $prev} {
                        return [DisplayHints <int>]
                    }
                    return [CompleteFromList ${text} \
                    [RemoveUsedOptions $line {-nocase -length <string>}]]
                }

                first -
                last { return [DisplayHints ?startIndex?] }

                map -
                match { return [DisplayHints <string>] }

                is {
                    if {"-failindex" == $prev} {
                        return [VarCompletion ${text}]
                    }
                    return [CompleteFromList ${text} \
                    [RemoveUsedOptions $line {-strict -failindex <string>}]]
                }

                bytelength {}
                index {}
                length {}
                range -
                replace { return [DisplayHints <last>] }
                repeat {}
            tolower -
            totitle -
            toupper {}
                tolower -
                totitle -
                toupper { return [DisplayHints ?last?] }

            trim -
            trimleft { if {![llength ${mod}]} { return ?chars? } }
            trimright -
            wordend -
            wordstart { if {![llength ${mod}]} { return <index> } }
                trim -
                trimleft -
                trimright {}
                wordend -
                wordstart {}
            }
        }
        default {
            switch -- $cmd {
                compare -
                equal {
                    if {"-length" == $prev} {
                        return [DisplayHints <int>]
                    }
                    return [CompleteFromList ${text} \
                    [RemoveUsedOptions $line {-nocase -length <string>}]]
                }

                is {
                    if {"-failindex" == $prev} {
                        return [VarCompletion ${text}]
                    }
                    return [CompleteFromList ${text} \
                    [RemoveUsedOptions $line {-strict -failindex <string>}]]
                }

                replace { return [DisplayHints ?newString?] }
            }
        }
    }
    return ""
}

proc complete(subst) {text start end line pos mod} {
    return [CompleteFromList ${text} [RemoveUsedOptions $line {
    set opts {-nobackslashes -nocommands -novariables}
        -nobackslashes -nocommands -novariables <string>}]]
    set opts [RemoveUsedOptions ${line} ${opts}]
    return [TryFromList ${mod} [concat ${opts} <string>]]
    return ""
}

proc complete(switch) {text start end line pos mod} {
    set prev [PreviousWord ${start} ${line}]
    if {[llength ${prev}] && "--" != $prev && \
        ("-" == [string index ${prev} 0] || 1 == $pos)} {
        set cmds [RemoveUsedOptions ${line} {
    set opts {-exact -glob -regexp --}
    set opts [RemoveUsedOptions ${line} ${opts} {--}]
    return [TryFromList ${mod} [concat ${opts} <string>]]
            -exact -glob -regexp --} {--}]
        if {[llength ${cmds}]} {
            return [string trim [CompleteFromList $text $cmds]]
        }
    } else {
        set virtual_pos [expr ${pos} - [FirstNonOption ${line}]]
        switch -- ${virtual_pos} {
            0 { return [DisplayHints <string>] }
            1 { return [DisplayHints <pattern>] }
            2 { return [DisplayHints <body>] }
            default { 
                switch [expr $virtual_pos % 2] {
                    0 { return [DisplayHints ?body?] }
                    1 { return [DisplayHints ?pattern?] }
                }
            }
        }
    }
    return ""
}

proc complete(tell) {text start end line pos mod} {
    if {1 == $pos} {
        return [ChannelId ${mod}]
    switch -- $pos {
        1 { return [ChannelId ${mod}] }
    }
    return ""
}

proc complete(time) {text start end line pos mod} {
    switch -- $pos {
        1 { return [DisplayHints <script>] }
        2 { return [DisplayHints ?count?] }
    }
    return ""
}

proc complete(trace) {text start end line pos mod} {
    set cmd [lindex ${line} 1]
    if {1 == $pos} {
        return [TryFromList ${mod} {variable vdelete vinfo}]
    } elseif {2 == $pos} {
        return [Format [uplevel 2 info vars "${mod}*"] ${mod}]
    } elseif {3 == $pos && "variable" == ${cmd}} {
        return [TryFromList ${mod} {r w u}]
    }
    set cmd [Lindex ${line} 1]
    switch -- $pos {
        1 {
            return [CompleteFromList ${mod} {variable vdelete vinfo}]
        }
        2 {
            return [CompleteFromList ${text} \
            [uplevel [info level] info vars "${mod}*"]]
        }
        3 {
            switch -- $cmd {
                variable -
                vdelete { return [CompleteFromList ${text} {r w u}] }
            }
        }
        4 {
            switch -- $cmd {
                variable -
                vdelete {
                    return [CompleteFromList $text [CommandCompletion $text]]
                }
            }
        }
    }
    return ""
}

proc complete(unknown) {text start end line pos mod} {
    switch -- $pos {
        1 {
            return [CompleteFromList $text [CommandCompletion $text]]
        }
        default { return [DisplayHints ?arg?] }
    }
    return ""
}

proc complete(unset) {text start end line pos mod} {
    return [VarCompletion ${text}]
}

proc complete(update) {text start end line pos mod} {
    if {1 == $pos && ![llength ${mod}]} {
        return idletasks
    switch -- $pos {
        1 { return idletasks }
    }
    return ""
}

proc complete(uplevel) {text start end line pos mod} {
    if {![llength ${mod}]} {
        if {1 == $pos} {
            return ?level?
        } elseif {2 == $pos} {
    set one [Lindex ${line} 1]
    switch -- $pos {
        1 {
            return [CompleteFromList $text "?level? [CommandCompletion $text]"]
        }
        2 {
            return <command>
        } elseif {3 == $pos} {
            return ?arg?
        } elseif {4 == $pos} {
            return ?...?
        }
    }
            if {"#" == [string index $one 0] || [regexp {^[0-9]*$} $one]} {
                return [CompleteFromList $text [CommandCompletion $text]]
            } else {
                return [DisplayHints ?arg?]
            }
        }
        default { return [DisplayHints ?arg?] }
    }
    return ""
}

proc complete(upvar) {text start end line pos mod} {
    if {![llength ${mod}]} {
        if {1 == $pos} {
            return ?level?
        } elseif {2 == $pos} {
            return <otherVar>
        } elseif {3 == $pos} {
            return <myVar>
        } elseif {4 == $pos} {
            return ?...?
    set one [Lindex ${line} 1]
    switch -- $pos {
        1 {
            return [DisplayHints {?level? <otherVar>}]
        }
        2 {
            if {"#" == [string index $one 0] || [regexp {^[0-9]*$} $one]} {
                return [DisplayHints <otherVar>]
            } else {
                return [DisplayHints <myVar>]
            }
        }
        3 {
            if {"#" == [string index $one 0] || [regexp {^[0-9]*$} $one]} {
                return [DisplayHints <myVar>]
            } else {
                return [DisplayHints ?otherVar?]
            }
        }
        default {
            set virtual_pos $pos
            if {"#" == [string index $one 0] || [regexp {^[0-9]*$} $one]} {
                incr virtual_pos
            }
            switch [expr $virtual_pos % 2] {
                0 { return [DisplayHints ?myVar?] }
                1 { return [DisplayHints ?otherVar?] }
            }
        }
    }
    return ""
}

proc complete(variable) {text start end line pos mod} {
    set modulo [expr $pos % 2]
    if {1 == ${modulo}} {
        return [VarCompletion ${mod}]
    } elseif {0 == ${modulo} && \
        ($text == "" || $text == "\"" || $text == "\{")} {
        set line [QuoteQuotes $line]
    switch -- $modulo {
        1 { return [VarCompletion ${text}] }
        0 {
            if {$text == "" || $text == "\"" || $text == "\{"} {
                set line [QuoteQuotes $line]
        incr pos -1
        if {[catch \
            "set value [list [uplevel [info level] set [lindex $line ${pos}]]]"\
            msg]} {
            return ""
        } else {
            return [Quote $value ${mod}]
                if {[catch [list set value [list [uplevel [info level] \
                    set [PreviousWord $start $line]]]] msg]
                } {
                    return ""
                } else {
                    return [Quote $value ${text}]
                }
            }
        }
    }
    return ""
}

proc complete(vwait) {text start end line pos mod} {
    if {1 == ${pos}} {
        return [VarCompletion ${mod}]
    switch -- $pos {
        1 { return [VarCompletion ${mod}] }
    }
    return ""
}

proc complete(unset) {text start end line pos mod} {
    return [VarCompletion ${text}]
proc complete(while) {text start end line pos mod} {
    switch -- $pos {
        1 -
        2 {
            return [BraceOrControlStatement $text $start $end $line $pos $mod]
        }
    }
    return ""
}

# -------------------------------------
#                  TK
# -------------------------------------

# generic widget configuration