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Tcl Source Code

Release Tcl 8.7b1 arises from the check-in with tag core-8.7-b1.

Highlighted differences between Tcl 8.7 and Tcl 8.6 are summarized below, with focus on changes important to programmers using the Tcl library and writing Tcl scripts.

Internationalization of text

• Full Unicode range of codepoints
• New encodings: utf-16/utf-32/ucs-2(le|be), CESU-8, etc.
• encoding options -profile, -failindex manage encoding of I/O.
• msgcat supports custom locale search list
• source defaults to -encoding utf-8

Zip filesystems and attached archives.

Unix notifiers available using epoll() or kqueue()

• relieves limits on file descriptors imposed by legacy select()

Notable incompatibilities

• No --disable-threads build option. Always thread-enabled.
• Windows platform needs Windows 7 or Windows Server 2008 R2 or later

New commands

• array default, array for
• chan isbinary
• coroinject, coroprobe
• clock add weekdays
• dict getwithdefault
• file tempdir, file home, file tildeexpand
• info commandtype
• ledit
• lpop
• lremove
• lseq
• package files
• string insert, string is dict
• tcl::process
• *::build-info
• readFile, writeFile, foreachLine

New command options

• regsub ... -command ...
• lsearch ... -stride ...
• clock scan ... -validate ...
• socket ... -nodelay ... -keepalive ...
• vwait controlled by several new options

Numbers

• 0dNNNN format to compel decimal interpretation.
• NN_NNN_NNN, underscores in numbers for optional readability
• Functions: isinf() isnan() isnormal() issubnormal() isunordered()
• fpclassify
• Function int() no longer truncates to word size

tcl::oo facilities

• private variable and methods
• method -export, method -unexport