/*
* This is a "yacc" specification of the syntax of RLISP. It is used
* to provide a (symbolic-mode) RLISP to Lisp translator that can be
* made freely available without reference to anybody apart from
* myself! The Lisp dialect generated is Standard Lisp and in all reality
* I intend it to be for use with CSL (my own Lisp). I am putting in
* a switch that causes generation of something a bit more like Common
* Lisp but please do not expect this to be fully sorted out and
* suitable for use with full Common Lisp: again it is tuned to my own
* private purposes...
*
* I will think about making this work with Bison as wall as Yacc but
* maybe I prefer the licence terms associated with Yacc. But it is quite
* certain that if you receive this code and can make it work with Bison
* you can use it internally: the only issues are to do with distribution,
* and if you are careful to use a sufficiently modern release of Bison
* its skeleton code may be distributed without bad license consequences.
*
* Usage:
* r2l -common -rights -Dname=val source1.red ... sourcen.red dest.lsp
*/
/*
* This code may be used and modified, and redistributed in binary
* or source form, subject to the "CCL Public License", which should
* accompany it. This license is a variant on the BSD license, and thus
* permits use of code derived from this in either open and commercial
* projects: but it does require that updates to this code be made
* available back to the originators of the package.
* Before merging other code in with this or linking this code
* with other packages or libraries please check that the license terms
* of the other material are compatible with those of this.
*/
%{
/*
* This is a "yacc" specification of the syntax of RLISP. It is used
* to provide a (symbolic-mode) RLISP to Lisp translator that can be
* made freely available without reference to anybody apart from
* myself! The Lisp dialect generated is Standard Lisp and in all reality
* I intend it to be for use with CSL (my own Lisp). I am putting in
* a switch that causes generation of something a bit more like Common
* Lisp but please do not expect this to be fully sorted out and
* suitable for use with full Common Lisp: again it is tuned to my own
* private purposes...
*
* I will think about making this work with Bison as wall as Yacc but
* maybe I prefer the licence terms associated with Yacc. But it is quite
* certain that if you receive this code and can make it work with Bison
* you can use it internally: the only issues are to do with distribution,
* and if you are careful to use a sufficiently modern release of Bison
* its skeleton code may be distributed without bad license consequences.
*
* Usage:
* r2l -common -rights -Dname=val source1.red ... sourcen.red dest.lsp
*/
/*
* This code may be used and modified, and redistributed in binary
* or source form, subject to the "CCL Public License", which should
* accompany it. This license is a variant on the BSD license, and thus
* permits use of code derived from this in either open and commercial
* projects: but it does require that updates to this code be made
* available back to the originators of the package.
* Before merging other code in with this or linking this code
* with other packages or libraries please check that the license terms
* of the other material are compatible with those of this.
*/
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <stdlib.h>
/*
* The next line is a bit of a cop-out!
*/
typedef long int intptr_t;
intptr_t *heap;
int heapfringe = 0;
int yyparse();
FILE *inputfile, *outputfile;
FILE *filestack[30];
int filestackp = 0;
char *defined_names[20];
int n_defined_names;
int common;
static char *rights_message[] =
{
"",
" This code may be used and modified, and redistributed in binary",
" or source form, subject to the \"CCL Public License\", which should",
" accompany it. This license is a variant on the BSD license, and thus",
" permits use of code derived from this in either open and commercial",
" projects: but it does require that updates to this code be made",
" available back to the originators of the package.",
" Before merging other code in with this or linking this code",
" with other packages or libraries please check that the license terms",
" of the other material are compatible with those of this.",
"",
NULL
};
int main(int argc, char *argv[])
{
int rights = 0;
inputfile = NULL;
outputfile = NULL;
common = 0;
/*
* If the very first arg is "-common" pick that off.
*/
if (argc > 1 &&
strcmp(argv[1], "-common") == 0)
{ common = 1;
printf("Common Lisp mode activated\n");
argv++;
argc--;
}
/*
* If the next arg is "-rights" then pick that off.
*/
if (argc > 1 &&
strcmp(argv[1], "-rights") == 0)
{ rights = 1;
printf("Will insert re-distribution rights notice\n");
argv++;
argc--;
}
/*
* Pick off initial command-line things of the form "-D..." and store the
* "..." bit.
*/
n_defined_names = 0;
while (argc > 1 &&
argv[1][0] == '-' &&
argv[1][1] == 'D')
{ if (n_defined_names < 20)
defined_names[n_defined_names++] = &argv[1][2];
argv++;
argc--;
}
/*
* If > 1 arg then final arg is destination. If only one arg then arg is
* a source!
*/
if (argc > 2)
{ if (strcmp(argv[--argc], "-") == 0) outputfile = stdout;
else outputfile = fopen(argv[argc], "w");
}
if (outputfile == NULL) outputfile = stdout;
if (common)
fprintf(outputfile, "\n;; RLISP to LISP converter. A C Norman 2004\n");
else fprintf(outputfile, "\n%% RLISP to LISP converter. A C Norman 2004\n");
fprintf(outputfile, "\n\n");
if (rights)
{ char **p = rights_message;
char *m;
while ((m = *p++) != NULL)
{ fprintf(outputfile, "%s%s\n", (common ? ";;" : "%"), m);
}
fprintf(outputfile, "\n\n");
}
heap = (intptr_t *)malloc(2000000); /* Rather arbitrary size! */
if (argc == 1) filestack[filestackp++] = stdin;
else while (--argc != 0)
{ if ((inputfile = fopen(argv[argc], "r")) == NULL)
printf("File %s not readable\n", argv[argc]);
else filestack[filestackp++] = inputfile;
}
inputfile = filestack[--filestackp];
yyparse();
fclose(outputfile);
printf("Finished...\n");
return 0;
}
char *lookup_name(char *s)
{
int i, n = strlen(s);
for (i=0; i<n_defined_names; i++)
{ char *w = defined_names[i]; /* name or name=value */
if (strncmp(s, w, n) == 0 &&
w[n] == 0 ||
w[n] == '=') return (w[n]==0 ? "" : &w[n+1]);
}
return NULL;
}
char linebuffer[128];
int linep = 0;
int ch = '\n';
int linecount = 1;
int nextch()
{
if (ch == -1) return ch; /* end of file sticks */
for (;;)
{ ch = getc(inputfile);
if (ch == -1 && filestackp != 0)
{ inputfile = filestack[--filestackp];
continue;
}
else break;
}
if (ch == '\n') linecount++;
linebuffer[127 & linep++] = ch;
return ch;
}
void yyerror(char *m)
{
int q = 0;
fprintf(stderr, "\nSyntax error (%s) around line %d\n", m, linecount);
if (linep >= 128) q = linep-128;
while (q != linep) fprintf(stderr, "%c", linebuffer[127 & q++]);
fprintf(stderr, "$$$");
while ((q = nextch()) != -1 && q != '\n') fprintf(stderr, "%c", q);
fprintf(stderr, "\n");
fflush(stderr);
exit(0);
}
typedef struct keyword_code
{
char *name;
intptr_t code;
} keyword_code;
static keyword_code operators[];
intptr_t find_symbol(char *s)
{
char *r = (char *)&heap[heapfringe];
int len = strlen(s);
strcpy(r, s);
heapfringe += (len+4)/4;
return (intptr_t)(r+1);
}
static int gennum = 1000;
intptr_t genlabel()
{
char name[32];
sprintf(name, "lab%d", gennum++);
return find_symbol(name);
}
intptr_t genvar()
{
char name[32];
sprintf(name, "var%d", gennum++);
return find_symbol(name);
}
static intptr_t yylex();
#define C_nil ((intptr_t)0)
#define qcar(x) (((intptr_t *)(x))[0])
#define qcdr(x) (((intptr_t *)(x))[1])
intptr_t cons(intptr_t a, intptr_t b)
{
intptr_t *r = &heap[heapfringe];
heapfringe += 2;
qcar(r) = a;
qcdr(r) = b;
return (intptr_t)r;
}
intptr_t ncons(intptr_t a)
{
intptr_t *r = &heap[heapfringe];
heapfringe += 2;
qcar(r) = a;
qcdr(r) = C_nil;
return (intptr_t)r;
}
intptr_t list1(intptr_t a)
{
return cons(a, C_nil);
}
intptr_t list2(intptr_t a, intptr_t b)
{
return cons(a, cons(b, C_nil));
}
intptr_t list3(intptr_t a, intptr_t b, intptr_t c)
{
return cons(a, cons(b, cons(c, C_nil)));
}
intptr_t list4(intptr_t a, intptr_t b, intptr_t c, intptr_t d)
{
return cons(a, cons(b, cons(c, cons(d, C_nil))));
}
intptr_t list5(intptr_t a, intptr_t b, intptr_t c, intptr_t d, intptr_t e)
{
return cons(a, cons(b, cons(c, cons(d, cons(e, C_nil)))));
}
intptr_t list6(intptr_t a, intptr_t b, intptr_t c, intptr_t d, intptr_t e, intptr_t f)
{
return cons(a, cons(b, cons(c, cons(d, cons(e, cons(f, C_nil))))));
}
intptr_t list7(intptr_t a, intptr_t b, intptr_t c, intptr_t d, intptr_t e, intptr_t f, intptr_t g)
{
return cons(a, cons(b, cons(c, cons(d,
cons(e, cons(f, cons(g, C_nil)))))));
}
intptr_t list8(intptr_t a, intptr_t b, intptr_t c, intptr_t d, intptr_t e, intptr_t f, intptr_t g, intptr_t h)
{
return cons(a, cons(b, cons(c, cons(d,
cons(e, cons(f, cons(g, cons(h, C_nil))))))));
}
intptr_t list9(intptr_t a, intptr_t b, intptr_t c, intptr_t d, intptr_t e, intptr_t f, intptr_t g, intptr_t h, intptr_t i)
{
return cons(a, cons(b, cons(c, cons(d,
cons(e, cons(f, cons(g, cons(h, cons(i, C_nil)))))))));
}
intptr_t append(intptr_t a, intptr_t b)
{
if (a == C_nil || ((a & 1) != 0)) return b;
else return cons(qcar(a), append(qcdr(a), b));
}
#define atom(x) ((intptr_t)(x)==0 || (((intptr_t)(x)) & 1) != 0)
int otlpos = 0;
int checkspace(int n)
{
if (otlpos + n < 78)
{ otlpos += n;
return 1;
}
fprintf(outputfile, "\n");
otlpos = n;
return 0;
}
static char common_name[256];
char *tocommon(char *s)
{
int easy = 1, c;
int p = 0, q = 0;
if (s[0] == '"') return s; /* a string */
if (isdigit(s[0])) return s; /* a number */
while ((c = s[p++]) != 0)
{ if (c == '!') c = s[p++];
common_name[q++] = c;
if (c == ':') common_name[q++] = c; /* double up ':' */
else if (!isalpha(c) && !isdigit(c) && c != '-' &&
c != '_' && c != '*' && c != '&' && c != '$') easy = 0;
}
common_name[q] = 0;
if (!easy)
{ common_name[q+1] = '|';
common_name[q+2] = 0;
while (q != 0)
{ common_name[q] = common_name[q-1];
q--;
}
common_name[0] = '|';
}
return common_name;
}
void print(intptr_t a)
{
if (a == C_nil)
{ checkspace(3);
fprintf(outputfile, "nil");
return;
}
else if (atom(a))
{ char *s = ((char *)a) - 1;
if (common) s = tocommon(s);
checkspace(strlen(s));
fprintf(outputfile, "%s", s);
return;
}
checkspace(1);
fprintf(outputfile, "(");
print(qcar(a));
a = qcdr(a);
while (!atom(a))
{ if (checkspace(1)) fprintf(outputfile, " ");
print(qcar(a));
a = qcdr(a);
}
if ((intptr_t)a != 0)
{ checkspace(2);
fprintf(outputfile, " .");
if (checkspace(1)) fprintf(outputfile, " ");
print(a);
}
checkspace(1);
fprintf(outputfile, ")");
}
static void evalorprint(intptr_t a)
{
if (a != C_nil && !atom(a))
{ intptr_t fn = qcar(a);
if (fn != C_nil && atom(fn) && strcmp((char *)fn-1, "in")==0)
{ a = qcar(qcdr(a));
if (a != C_nil && !atom(a))
{ fn = qcar(a);
if (fn != C_nil && atom(fn) &&
strcmp((char *)fn-1, "list")==0)
{ a = qcar(qcdr(a));
if (a != C_nil && atom(a))
{ FILE *f;
char filename[200];
char *s = (char *)a-1;
if (*s == '"')
{ s++;
s[strlen(s)-1] = 0;
}
if (*s != '$') strcpy(filename, s);
else
{ char parmname[200];
int k=0;
char *val;
s++;
parmname[k++] = '@';
while (*s != '/') parmname[k++] = *s++;
parmname[k] = 0;
val = lookup_name(parmname);
if (val == NULL) val = ".";
strcpy(filename, val);
strcat(filename, s);
}
f = fopen(filename, "r");
if (f == NULL)
{ printf("File \"%s\" not found\n", filename);
exit(1);
}
filestack[filestackp++] = inputfile;
inputfile = f;
printf("READING FILE <%s>\n", filename);
return;
}
}
}
}
}
print(a);
}
#define sym_0 find_symbol("0")
#define sym_car find_symbol("car")
#define sym_cdr find_symbol("cdr")
/* I have reversip available even in Common Lisp mode for nreverse */
#define sym_reversip find_symbol("reversip")
#define sym_plus find_symbol("plus")
#define sym_minus find_symbol("minus")
#define sym_minusp find_symbol("minusp")
#define sym_getv find_symbol("getv")
#define sym_difference find_symbol("difference")
#define sym_times find_symbol("times")
#define sym_quotient find_symbol("quotient")
#define sym_expt find_symbol("expt")
#define sym_cons find_symbol("cons")
#define sym_list find_symbol("list")
#define sym_progn find_symbol("progn")
#define sym_prog find_symbol("prog")
#define sym_de find_symbol("de")
#define sym_dm find_symbol("dm")
#define sym_ds find_symbol("ds")
#define sym_greaterp find_symbol("greaterp")
#define sym_lessp find_symbol("lessp")
#define sym_equal find_symbol("equal")
#define sym_setq find_symbol("setq")
#define sym_and find_symbol("and")
#define sym_or find_symbol("or")
#define sym_not find_symbol("not")
#define sym_member find_symbol("member")
#define sym_memq find_symbol("memq")
#define sym_neq find_symbol("neq")
#define sym_eq find_symbol("eq")
#define sym_geq find_symbol("geq")
#define sym_leq find_symbol("leq")
#define sym_freeof find_symbol("freeof")
#define sym_symbolic find_symbol("symbolic")
#define sym_algebraic find_symbol("algebraic")
#define sym_expr find_symbol("expr")
#define sym_macro find_symbol("macro")
#define sym_smacro find_symbol("smacro")
#define sym_procedure find_symbol("procedure")
#define sym_for find_symbol("for")
#define sym_step find_symbol("step")
#define sym_until find_symbol("until")
#define sym_each find_symbol("each")
#define sym_foreach find_symbol("foreach")
#define sym_in find_symbol("in")
#define sym_on find_symbol("on")
#define sym_do find_symbol("do")
#define sym_collect find_symbol("collect")
#define sym_sum find_symbol("sum")
#define sym_if find_symbol("if")
#define sym_then find_symbol("then")
#define sym_else find_symbol("else")
#define sym_cond find_symbol("cond")
#define sym_repeat find_symbol("repeat")
#define sym_while find_symbol("while")
#define sym_begin find_symbol("begin")
#define sym_end find_symbol("end")
#define sym_lsect find_symbol("<<")
#define sym_rsect find_symbol(">>")
#define sym_go find_symbol("go")
#define sym_to find_symbol("to")
#define sym_t find_symbol("t")
#define sym_goto find_symbol("goto")
#define sym_scalar find_symbol("scalar")
#define sym_integer find_symbol("integer")
#define sym_lambda find_symbol("lambda")
#define sym_symbol find_symbol("symbol")
#define sym_number find_symbol("number")
#define sym_string find_symbol("string")
#define sym_quoted find_symbol("quoted")
#define sym_return find_symbol("return")
#define sym_where find_symbol("where")
#define sym_rlistat find_symbol("rlistat")
#define sym_endstat find_symbol("endstat")
#define sym_null find_symbol("null")
intptr_t make_where(intptr_t body, intptr_t var, intptr_t val)
{
return list2(
list3(sym_lambda, list1(var), body),
val);
}
intptr_t make_in_do(intptr_t var, intptr_t input, intptr_t body)
{
intptr_t lab1 = genlabel();
intptr_t var1 = genvar();
return list8(sym_prog, list1(var1),
list3(sym_setq, var1, input),
lab1,
list2(sym_cond,
list2(list2(sym_null, var1),
list2(sym_return, C_nil))),
list4(sym_prog, list1(var), list3(sym_setq, var, list2(sym_car, var1)), body),
list3(sym_setq, var1, list2(sym_cdr, var1)),
list2(sym_go, lab1));
}
intptr_t make_on_do(intptr_t var, intptr_t input, intptr_t body)
{
intptr_t lab1 = genlabel();
return list8(sym_prog, list1(var),
list3(sym_setq, var, input),
lab1,
list2(sym_cond,
list2(list2(sym_null, var),
list2(sym_return, C_nil))),
body,
list3(sym_setq, var, list2(sym_cdr, var)),
list2(sym_go, lab1));
}
intptr_t make_in_collect(intptr_t var, intptr_t input, intptr_t body)
{
intptr_t lab1 = genlabel();
intptr_t var1 = genvar();
intptr_t var2 = genvar();
return list8(sym_prog, list2(var1, var2),
list3(sym_setq, var1, input),
lab1,
list2(sym_cond,
list2(list2(sym_null, var1),
list2(sym_return, list2(sym_reversip, var2)))),
list4(sym_prog, list1(var),
list3(sym_setq, var, list2(sym_car, var1)),
list3(sym_setq, var2, list3(sym_cons, body, var2))),
list3(sym_setq, var1, list2(sym_cdr, var1)),
list2(sym_go, lab1));
}
intptr_t make_on_collect(intptr_t var, intptr_t input, intptr_t body)
{
intptr_t lab1 = genlabel();
intptr_t var2 = genvar();
return list8(sym_prog, list1(var),
list3(sym_setq, var, input),
lab1,
list2(sym_cond,
list2(list2(sym_null, var),
list2(sym_return, list2(sym_reversip, var2)))),
list3(sym_setq, var2, list3(sym_cons, body, var2)),
list3(sym_setq, var, list2(sym_cdr, var)),
list2(sym_go, lab1));
}
intptr_t make_in_sum(intptr_t var, intptr_t input, intptr_t body)
{
intptr_t lab1 = genlabel();
intptr_t var1 = genvar();
intptr_t var2 = genvar();
return list9(sym_prog, list2(var1, var2),
list3(sym_setq, var1, input),
list3(sym_setq, var2, sym_0),
lab1,
list2(sym_cond,
list2(list2(sym_null, var1),
list2(sym_return, var2))),
list4(sym_prog, list1(var),
list3(sym_setq, var, list2(sym_car, var1)),
list3(sym_setq, var2, list3(sym_plus, body, var2))),
list3(sym_setq, var1, list2(sym_cdr, var1)),
list2(sym_go, lab1));
}
intptr_t make_foreach(intptr_t var, intptr_t type, intptr_t input, intptr_t action, intptr_t body)
{
intptr_t inon = 0, docollect = 0;
if (strcmp((char *)type-1, "on") == 0) inon = 1;
if (strcmp((char *)action-1, "collect") == 0) docollect = 1;
else if (strcmp((char *)action-1, "sum") == 0) docollect = 2;
switch (inon+2*docollect)
{
case 0: /* in/do */
return make_in_do(var, input, body);
case 1: /* on/do */
return make_on_do(var, input, body);
case 2: /* in/collect */
return make_in_collect(var, input, body);
case 3: /* on/collect */
return make_on_collect(var, input, body);
case 4: /* in/sum */
return make_in_sum(var, input, body);
case 5: /* on/sum WHICH CAN NOT MAKE SENSE */
default:
return C_nil;
}
}
intptr_t for_do(intptr_t var, intptr_t init, intptr_t step, intptr_t end, intptr_t body)
{
intptr_t lab1 = genlabel();
return list8(sym_prog, list1(var),
list3(sym_setq, var, init),
lab1,
list2(sym_cond,
list2(list2(sym_minusp,
list3(sym_times, step,
list3(sym_difference, end, var))),
list2(sym_return, C_nil))),
body,
list3(sym_setq, var, list3(sym_plus, var, step)),
list2(sym_go, lab1));
}
intptr_t for_collect(intptr_t var, intptr_t init, intptr_t step, intptr_t end, intptr_t body)
{
intptr_t lab1 = genlabel();
intptr_t var1 = genvar();
return list8(sym_prog, list2(var, var1),
list3(sym_setq, var, init),
lab1,
list2(sym_cond,
list2(list2(sym_minusp,
list3(sym_times, step,
list3(sym_difference, end, var))),
list2(sym_return, list2(sym_reversip, var1)))),
list3(sym_setq, var1, list3(sym_cons, body, var1)),
list3(sym_setq, var, list3(sym_plus, var, step)),
list2(sym_go, lab1));
}
intptr_t for_sum(intptr_t var, intptr_t init, intptr_t step, intptr_t end, intptr_t body)
{
intptr_t lab1 = genlabel();
intptr_t var1 = genvar();
return list9(sym_prog, list2(var, var1),
list3(sym_setq, var, init),
list3(sym_setq, var1, sym_0),
lab1,
list2(sym_cond,
list2(list2(sym_minusp,
list3(sym_times, step,
list3(sym_difference, end, var))),
list2(sym_return, var1))),
list3(sym_setq, var1, list3(sym_plus, body, var1)),
list3(sym_setq, var, list3(sym_plus, var, step)),
list2(sym_go, lab1));
}
intptr_t make_for(intptr_t var, intptr_t init, intptr_t step, intptr_t end, intptr_t action, intptr_t body)
{
intptr_t docollect = 0;
if (strcmp((char *)action-1, "collect") == 0) docollect = 1;
else if (strcmp((char *)action-1, "sum") == 0) docollect = 2;
switch (docollect)
{
case 0: /* do */
return for_do(var, init, step, end, body);
case 1: /* collect */
return for_collect(var, init, step, end, body);
case 2: /* sum */
return for_sum(var, init, step, end, body);
default:
return C_nil;
}
}
intptr_t lex_eof = 0;
%}
%union
{
intptr_t LO;
}
%token <LO> SETQ
%token <LO> AND
%token <LO> OR
%token <LO> NOT
%token <LO> MEMBER
%token <LO> MEMQ
%token <LO> NEQ
%token <LO> EQ
%token <LO> GEQ
%token <LO> LEQ
%token <LO> FREEOF
%token <LO> SYMBOLIC
%token <LO> ALGEBRAIC
%token <LO> EXPR
%token <LO> MACRO
%token <LO> SMACRO
%token <LO> PROCEDURE
%token <LO> FOR
%token <LO> STEP
%token <LO> UNTIL
%token <LO> EACH
%token <LO> FOREACH
%token <LO> IN
%token <LO> ON
%token <LO> DO
%token <LO> COLLECT
%token <LO> SUM
%token <LO> IF
%token <LO> THEN
%token <LO> ELSE
%token <LO> REPEAT
%token <LO> WHILE
%token <LO> BEGIN
%token <LO> END
%token <LO> ENDFILE
%token <LO> LSECT
%token <LO> RSECT
%token <LO> GO
%token <LO> TO
%token <LO> GOTO
%token <LO> SCALAR
%token <LO> INTEGER
%token <LO> LAMBDA
%token <LO> SYMBOL
%token <LO> NUMBER
%token <LO> STRING
%token <LO> LIST
%token <LO> RETURN
%token <LO> WHERE
%token <LO> RLISTAT
%token <LO> ENDSTAT
%token <LO> HASHIF
%token <LO> HASHELSE
%token <LO> HASHELIF
%token <LO> HASHENDIF
%%
/*
* The grammar here is ambiguous or delicate in several areas:
* (a) It has the standard "dangling else" problem.
* (b) If R is a word tagged as RLIS, then R takes as its operands
* a whole bunch of things linked by commas. At present I have this
* grammar ambiguous on
* R1 a, b, c, R2 d, e, f;
* where R2 could (as far as the grammar is concerned) be being
* given one, two or three arguments. This problem arises if the
* operands of R may themselves end in an R. This is harded to avoid
* than I at first thought - one might well want conditionals in the
* are list of an R, but then
* R1 a, IF x THEN R2 b, c;
* comes and bites. I guess this is a "dangling comma" problem.
* The above two problems are resolved by the parser genarator favouring
* shift over reduce in the ambiguous cases.
* (c) "IN", "ON" are both keywords, as used in
* for each x in y do ...
* and words with the RLISTAT property. This is sordid! Similarly
* "END" has a dual use. This is coped with by making special provision
* in the grammar for these cases.
*/
wholefile : ENDFILE {
if (common) fprintf(outputfile, "\n;; end of file\n");
else fprintf(outputfile, "\n%% end of file\n");
exit(0);
}
| command wholefile
command : cmnd sep { evalorprint($<LO>1);
fprintf(outputfile, "\n\n");
otlpos = 0;
heapfringe = 0;
}
| proc_type sep
| END
| END sep
;
sep : ';'
| '$'
;
proc_type : SYMBOLIC { $<LO>$ = sym_symbolic; }
| ALGEBRAIC { $<LO>$ = sym_algebraic; }
;
proc_qual : EXPR { $<LO>$ = sym_de; }
| MACRO { $<LO>$ = sym_dm; }
| SMACRO { $<LO>$ = sym_ds; }
;
sym_list : ')' { $<LO>$ = C_nil; }
| ',' SYMBOL sym_list { $<LO>$ = cons($<LO>2, $<LO>3); }
;
/*
* RLISP seems to want to be able to write
* procedure a >= b; ...
* with an infix operator being defined!
*/
infix : SETQ { $<LO>$ = sym_setq; }
| OR { $<LO>$ = sym_or; }
| AND { $<LO>$ = sym_and; }
| MEMBER { $<LO>$ = sym_member; }
| MEMQ { $<LO>$ = sym_memq; }
| '=' { $<LO>$ = sym_equal; }
| NEQ { $<LO>$ = sym_neq; }
| EQ { $<LO>$ = sym_eq; }
| GEQ { $<LO>$ = sym_geq; }
| '>' { $<LO>$ = sym_greaterp; }
| LEQ { $<LO>$ = sym_leq; }
| '<' { $<LO>$ = sym_lessp; }
| FREEOF { $<LO>$ = sym_freeof; }
| '+' { $<LO>$ = sym_plus; }
| '-' { $<LO>$ = sym_difference; }
| '*' { $<LO>$ = sym_times; }
| '/' { $<LO>$ = sym_quotient; }
| '^' { $<LO>$ = sym_expt; }
| '.' { $<LO>$ = sym_cons; }
;
prefix : NOT { $<LO>$ = sym_not; }
| '+' { $<LO>$ = sym_plus; }
| '-' { $<LO>$ = sym_minus; }
;
proc_head : SYMBOL { $<LO>$ = cons($<LO>1, C_nil); }
| SYMBOL SYMBOL { $<LO>$ = list2($<LO>1, $<LO>2); }
| SYMBOL '(' ')' { $<LO>$ = cons($<LO>1, C_nil); }
| SYMBOL '(' SYMBOL sym_list
{ $<LO>$ = cons($<LO>1, cons($<LO>3, $<LO>4)); }
| prefix SYMBOL { $<LO>$ = list2($<LO>1, $<LO>2); }
| SYMBOL infix SYMBOL { $<LO>$ = list3($<LO>2, $<LO>1, $<LO>3); }
;
proc_def : PROCEDURE proc_head sep cmnd
{ $<LO>$ = list4(sym_de, qcar($<LO>2), qcdr($<LO>2), $<LO>4); }
| proc_type PROCEDURE proc_head sep cmnd
{ $<LO>$ = list4(sym_de, qcar($<LO>3), qcdr($<LO>3), $<LO>5); }
| proc_qual PROCEDURE proc_head sep cmnd
{ $<LO>$ = list4($<LO>1, qcar($<LO>3), qcdr($<LO>3), $<LO>5); }
| proc_type proc_qual PROCEDURE proc_head sep cmnd
{ $<LO>$ = list4($<LO>2, qcar($<LO>4), qcdr($<LO>4), $<LO>6); }
;
rlistat : RLISTAT
| IN { $<LO>$ = sym_in; }
| ON { $<LO>$ = sym_on; }
;
rltail : expr { $<LO>$ = cons($<LO>1, C_nil); }
| expr ',' rltail { $<LO>$ = cons($<LO>1, $<LO>3); }
;
/*
* The category "cmnd" really only needs separating out to try to
* control the comma-lists in RLIS things.
*/
cmnd : expr
| rlistat rltail { $<LO>$ = list2($<LO>1, cons(sym_list, $<LO>2)); }
;
/*
* As written here the grammar exhibits the traditional "dangling else"
* ambiguity. This must be resolved as SHIFT rather than REDUCE for
* the proper results to emerge.
*/
if_stmt : IF expr THEN cmnd ELSE cmnd
{ $<LO>$ = list3(sym_cond,
list2($<LO>2, $<LO>4),
list2(sym_t, $<LO>6)); }
| IF expr THEN cmnd { $<LO>$ = list2(sym_cond,
list2($<LO>2, $<LO>4)); }
;
for_update : ':' expr { $<LO>$ = cons(find_symbol("1"), $<LO>2); }
| STEP expr UNTIL expr { $<LO>$ = cons($<LO>2, $<LO>4); }
;
for_action : DO { $<LO>$ = sym_do; }
| SUM { $<LO>$ = sym_sum; }
| COLLECT { $<LO>$ = sym_collect; }
;
for_inon : IN { $<LO>$ = sym_in; }
| ON { $<LO>$ = sym_on; }
;
for_stmt : FOR SYMBOL SETQ expr for_update for_action cmnd
{ $<LO>$ = make_for($<LO>2, $<LO>4, qcar($<LO>5), qcdr($<LO>5), $<LO>6, $<LO>7); }
| FOR EACH SYMBOL for_inon expr for_action cmnd
{ $<LO>$ = make_foreach($<LO>3, $<LO>4, $<LO>5, $<LO>6, $<LO>7); }
| FOREACH SYMBOL for_inon expr for_action cmnd
{ $<LO>$ = make_foreach($<LO>2, $<LO>3, $<LO>4, $<LO>5, $<LO>6); }
;
while_stmt : WHILE expr DO cmnd {
intptr_t lab1 = genlabel();
$<LO>$ = list6(sym_prog, C_nil, lab1,
list2(sym_cond, list2(list2(sym_null, $<LO>2), list2(sym_return, C_nil))),
$<LO>4,
list2(sym_go, lab1)); }
;
repeat_stmt : REPEAT cmnd UNTIL expr {
intptr_t lab1 = genlabel();
$<LO>$ = list5(sym_prog, C_nil, lab1,
$<LO>2,
list2(sym_cond, list2(list2(sym_null, $<LO>4), list2(sym_go, lab1)))); }
;
return_stmt : RETURN { $<LO>$ = list2(sym_return, C_nil); }
| RETURN expr { $<LO>$ = list2(sym_return, $<LO>2); }
;
goto_stmt : GOTO SYMBOL { $<LO>$ = list2(sym_go, $<LO>2); }
| GO SYMBOL { $<LO>$ = list2(sym_go, $<LO>2); }
| GO TO SYMBOL { $<LO>$ = list2(sym_go, $<LO>3); }
;
group_tail : RSECT { $<LO>$ = C_nil; }
| sep RSECT { $<LO>$ = C_nil; }
| sep cmnd group_tail { $<LO>$ = cons($<LO>2, $<LO>3); }
;
group_expr : LSECT cmnd group_tail{ $<LO>$ = cons(sym_progn, cons($<LO>2, $<LO>3)); }
;
scalar_tail : sep { $<LO>$ = C_nil; }
| ',' SYMBOL scalar_tail
{ $<LO>$ = cons($<LO>2, $<LO>3); }
| ',' INTEGER scalar_tail
{ $<LO>$ = cons($<LO>2, $<LO>3); }
;
scalar_def : SCALAR SYMBOL scalar_tail
{ $<LO>$ = cons($<LO>2, $<LO>3); }
scalar_def : INTEGER SYMBOL scalar_tail
{ $<LO>$ = cons($<LO>2, $<LO>3); }
;
scalar_defs : scalar_def
| scalar_defs scalar_def
{ $<LO>$ = append($<LO>1, $<LO>2); }
;
block_tail : END { $<LO>$ = C_nil; }
| cmnd END { $<LO>$ = cons($<LO>1, C_nil); }
| SYMBOL ':' block_tail{ $<LO>$ = cons($<LO>1, $<LO>3); }
| cmnd sep block_tail { $<LO>$ = cons($<LO>1, $<LO>3); }
| sep block_tail { $<LO>$ = $<LO>2; }
;
block_expr : BEGIN scalar_defs block_tail
{ $<LO>$ = cons(sym_prog, cons($<LO>2, $<LO>3)); }
| BEGIN block_tail { $<LO>$ = cons(sym_prog, cons(C_nil, $<LO>2)); }
;
lambda_vars : sep { $<LO>$ = C_nil; }
| ',' SYMBOL lambda_vars
{ $<LO>$ = cons($<LO>2, $<LO>3); }
;
lambda_expr : LAMBDA SYMBOL lambda_vars cmnd
{ $<LO>$ = list3(sym_lambda, ncons($<LO>2), $<LO>3); }
| LAMBDA '(' ')' sep cmnd
{ $<LO>$ = list3(sym_lambda, C_nil, $<LO>5); }
| LAMBDA '(' SYMBOL sym_list sep cmnd
{ $<LO>$ = list3(sym_lambda, cons($<LO>3, $<LO>4), $<LO>6); }
;
/*
* In what follows rx0 is an expression which MUST end if a key-command,
* while lx0 is an expression which MUST NOT.
*/
expr : rx0
| lx0
;
rx0 : lx0 WHERE SYMBOL '=' rx1
{ $<LO>$ = make_where($<LO>1, $<LO>3, $<LO>5); }
| rx1
;
lx0 : lx0 WHERE SYMBOL '=' lx1
{ $<LO>$ = make_where($<LO>1, $<LO>3, $<LO>5); }
| lx1
;
rx1 : lx2 SETQ rx1 { $<LO>$ = list3(sym_setq, $<LO>1, $<LO>3); }
| rx2
;
lx1 : lx2 SETQ lx1 { $<LO>$ = list3(sym_setq, $<LO>1, $<LO>3); }
| lx2
;
rx2tail : rx3 { $<LO>$ = ncons($<LO>1); }
| lx3 OR rx2tail { $<LO>$ = cons($<LO>1, $<LO>3); }
rx2 : lx3 OR rx2tail { $<LO>$ = cons(sym_or, cons($<LO>1, $<LO>3)); }
| rx3
;
lx2tail : lx3 { $<LO>$ = ncons($<LO>1); }
| lx3 OR lx2tail { $<LO>$ = cons($<LO>1, $<LO>3); }
lx2 : lx3 OR lx2tail { $<LO>$ = cons(sym_or, cons($<LO>1, $<LO>3)); }
| lx3
;
rx3tail : rx4 { $<LO>$ = ncons($<LO>1); }
| lx4 AND rx3tail { $<LO>$ = cons($<LO>1, $<LO>3); }
rx3 : lx4 AND rx3tail { $<LO>$ = cons(sym_and, cons($<LO>1, $<LO>3)); }
| rx4
;
lx3tail : lx4 { $<LO>$ = ncons($<LO>1); }
| lx4 AND lx3tail { $<LO>$ = cons($<LO>1, $<LO>3); }
lx3 : lx4 AND lx3tail { $<LO>$ = cons(sym_and, cons($<LO>1, $<LO>3)); }
| lx4
;
rx4 : NOT rx4 { $<LO>$ = list2(sym_not, $<LO>2); }
| rx5
;
lx4 : NOT lx4 { $<LO>$ = list2(sym_not, $<LO>2); }
| lx5
;
rx5 : lx6 MEMBER ry6 { $<LO>$ = list3(sym_member, $<LO>1, $<LO>3); }
| lx6 MEMQ ry6 { $<LO>$ = list3(sym_memq, $<LO>1, $<LO>3); }
| lx6 '=' ry6 { $<LO>$ = list3(sym_equal, $<LO>1, $<LO>3); }
| lx6 NEQ ry6 { $<LO>$ = list3(sym_neq, $<LO>1, $<LO>3); }
| lx6 EQ ry6 { $<LO>$ = list3(sym_eq, $<LO>1, $<LO>3); }
| lx6 GEQ ry6 { $<LO>$ = list3(sym_geq, $<LO>1, $<LO>3); }
| lx6 '>' ry6 { $<LO>$ = list3(sym_greaterp, $<LO>1, $<LO>3); }
| lx6 LEQ ry6 { $<LO>$ = list3(sym_leq, $<LO>1, $<LO>3); }
| lx6 '<' ry6 { $<LO>$ = list3(sym_lessp, $<LO>1, $<LO>3); }
| lx6 FREEOF ry6 { $<LO>$ = list3(sym_freeof, $<LO>1, $<LO>3); }
| rx6
;
lx5 : lx6 MEMBER ly6 { $<LO>$ = list3(sym_member, $<LO>1, $<LO>3); }
| lx6 MEMQ ly6 { $<LO>$ = list3(sym_memq, $<LO>1, $<LO>3); }
| lx6 '=' ly6 { $<LO>$ = list3(sym_equal, $<LO>1, $<LO>3); }
| lx6 NEQ ly6 { $<LO>$ = list3(sym_neq, $<LO>1, $<LO>3); }
| lx6 EQ ly6 { $<LO>$ = list3(sym_eq, $<LO>1, $<LO>3); }
| lx6 GEQ ly6 { $<LO>$ = list3(sym_geq, $<LO>1, $<LO>3); }
| lx6 '>' ly6 { $<LO>$ = list3(sym_greaterp, $<LO>1, $<LO>3); }
| lx6 LEQ ly6 { $<LO>$ = list3(sym_leq, $<LO>1, $<LO>3); }
| lx6 '<' ly6 { $<LO>$ = list3(sym_lessp, $<LO>1, $<LO>3); }
| lx6 FREEOF ly6 { $<LO>$ = list3(sym_freeof, $<LO>1, $<LO>3); }
| lx6
;
ry6 : NOT ry6 { $<LO>$ = list2(sym_not, $<LO>2); }
| rx6
;
ly6 : NOT ly6 { $<LO>$ = list2(sym_not, $<LO>2); }
| lx6
;
rx6tail : ry6a { $<LO>$ = ncons($<LO>1); }
| ly6a '+' rx6tail { $<LO>$ = cons($<LO>1, $<LO>3); }
rx6 : lx6a '+' rx6tail { $<LO>$ = cons(sym_plus, cons($<LO>1, $<LO>3)); }
| rx6a
;
lx6tail : ly6a { $<LO>$ = ncons($<LO>1); }
| ly6a '+' lx6tail { $<LO>$ = cons($<LO>1, $<LO>3); }
lx6 : lx6a '+' lx6tail { $<LO>$ = cons(sym_plus, cons($<LO>1, $<LO>3)); }
| lx6a
;
ry6a : NOT ry6a { $<LO>$ = list2(sym_not, $<LO>2); }
| rx6a
;
rx6a : lx6a '-' ry7 { $<LO>$ = list3(sym_difference, $<LO>1, $<LO>3); }
| rx7
;
ly6a : NOT ly6a { $<LO>$ = list2(sym_not, $<LO>2); }
| lx6a
;
lx6a : lx6a '-' ly7 { $<LO>$ = list3(sym_difference, $<LO>1, $<LO>3); }
| lx7
;
ry7 : NOT ry7 { $<LO>$ = list2(sym_not, $<LO>2); }
| rx7
;
rx7 : '+' ry7 { $<LO>$ = $<LO>2; }
| '-' ry7 { $<LO>$ = list2(sym_minus, $<LO>2); }
| rx8
;
ly7 : NOT ly7 { $<LO>$ = list2(sym_not, $<LO>2); }
| lx7
;
lx7 : '+' ly7 { $<LO>$ = $<LO>2; }
| '-' ly7 { $<LO>$ = list2(sym_minus, $<LO>2); }
| lx8
;
rx8tail : ry9 { $<LO>$ = ncons($<LO>1); }
| ly9 '*' rx8tail { $<LO>$ = cons($<LO>1, $<LO>3); }
rx8 : lx9 '*' rx8tail { $<LO>$ = cons(sym_times, cons($<LO>1, $<LO>3)); }
| rx9
;
lx8tail : ly9 { $<LO>$ = ncons($<LO>1); }
| ly9 '*' lx8tail { $<LO>$ = cons($<LO>1, $<LO>3); }
lx8 : lx9 '*' lx8tail { $<LO>$ = cons(sym_times, cons($<LO>1, $<LO>3)); }
| lx9
;
ry9 : NOT ry9 { $<LO>$ = list2(sym_not, $<LO>2); }
| '+' ry9 { $<LO>$ = $<LO>2; }
| '-' ry9 { $<LO>$ = list2(sym_minus, $<LO>2); }
| rx9
;
rx9 : lx9 '/' ry10 { $<LO>$ = list3(sym_quotient, $<LO>1, $<LO>3); }
| rx10
;
ly9 : NOT ly9 { $<LO>$ = list2(sym_not, $<LO>2); }
| '+' ly9 { $<LO>$ = $<LO>2; }
| '-' ly9 { $<LO>$ = list2(sym_minus, $<LO>2); }
| lx9
;
lx9 : lx9 '/' ly10 { $<LO>$ = list3(sym_quotient, $<LO>1, $<LO>3); }
| lx10
;
ly10 : NOT ly10 { $<LO>$ = list2(sym_not, $<LO>2); }
| '+' ly10 { $<LO>$ = $<LO>2; }
| '-' ly10 { $<LO>$ = list2(sym_minus, $<LO>2); }
| lx10
;
lx10 : lx11 '^' ly10 { $<LO>$ = list3(sym_expt, $<LO>1, $<LO>3); }
| lx11
;
ry10 : NOT ry10 { $<LO>$ = list2(sym_not, $<LO>2); }
| '+' ry10 { $<LO>$ = $<LO>2; }
| '-' ry10 { $<LO>$ = list2(sym_minus, $<LO>2); }
| rx10
;
rx10 : lx11 '^' ry10 { $<LO>$ = list3(sym_expt, $<LO>1, $<LO>3); }
| rx11
;
ry11 : NOT ry11 { $<LO>$ = list2(sym_not, $<LO>2); }
| '+' ry11 { $<LO>$ = $<LO>2; }
| '-' ry11 { $<LO>$ = list2(sym_minus, $<LO>2); }
| rx11
;
rx11 : x12 '.' ry11 { $<LO>$ = list3(sym_cons, $<LO>1, $<LO>3); }
| if_stmt
| for_stmt
| while_stmt
| repeat_stmt
| return_stmt
| goto_stmt
| lambda_expr
| proc_def
| ENDSTAT { $<LO>$ = ncons($<LO>1); }
;
ly11 : NOT ly11 { $<LO>$ = list2(sym_not, $<LO>2); }
| '+' ly11 { $<LO>$ = $<LO>2; }
| '-' ly11 { $<LO>$ = list2(sym_minus, $<LO>2); }
| lx11
;
lx11 : x12 '.' ly11 { $<LO>$ = list3(sym_cons, $<LO>1, $<LO>3); }
| x12
;
arg_list : ')' { $<LO>$ = C_nil; }
| '}' { $<LO>$ = C_nil; }
| ',' expr arg_list { $<LO>$ = cons($<LO>2, $<LO>3); }
;
parened : '(' expr ')' { $<LO>$ = $<LO>2; }
;
commaparened : '(' expr ',' expr arg_list { $<LO>$ = cons($<LO>2, cons($<LO>4,$<LO>5)); }
;
x12notparened : x13b '[' expr ']' { $<LO>$ = list3(sym_getv, $<LO>1, $<LO>3); }
| x13b '(' ')' { $<LO>$ = cons($<LO>1, C_nil); }
| x13b parened { $<LO>$ = cons($<LO>1, cons($<LO>2, C_nil)); }
| x13b commaparened { $<LO>$ = cons($<LO>1, $<LO>2); }
| x13b x12notparened { $<LO>$ = list2($<LO>1, $<LO>2); }
| x13b
;
x12 : x12notparened { $<LO>$ = $<LO>1; }
| parened { $<LO>$ = $<LO>1; }
| '{' '}' { $<LO>$ = C_nil; }
| '{' expr arg_list { $<LO>$ = cons(sym_list, cons($<LO>2, $<LO>3)); }
| SETQ commaparened { $<LO>$ = cons(sym_setq, $<LO>2); }
| OR commaparened { $<LO>$ = cons(sym_or, $<LO>2); }
| AND commaparened { $<LO>$ = cons(sym_and, $<LO>2); }
| MEMBER commaparened { $<LO>$ = cons(sym_member, $<LO>2); }
| MEMQ commaparened { $<LO>$ = cons(sym_memq, $<LO>2); }
| NEQ commaparened { $<LO>$ = cons(sym_neq, $<LO>2); }
| EQ commaparened { $<LO>$ = cons(sym_eq, $<LO>2); }
| GEQ commaparened { $<LO>$ = cons(sym_geq, $<LO>2); }
| LEQ commaparened { $<LO>$ = cons(sym_leq, $<LO>2); }
| FREEOF commaparened { $<LO>$ = cons(sym_freeof, $<LO>2); }
;
x13b : SYMBOL
| NUMBER
| STRING
| LIST
| group_expr
| block_expr
;
%%
static keyword_code operators[] =
{
{"plus", -1},
{"minus", -1},
{"getv", -1},
{"difference", -1},
{"times", -1},
{"quotient", -1},
{"expt", -1},
{"cons", -1},
{"list", -1},
{"progn", -1},
{"prog", -1},
{"de", -1},
{"dm", -1},
{"ds", -1},
{"greaterp", -1},
{"lessp", -1},
{"equal", -1},
{"setq", SETQ},
{"and", AND},
{"or", OR},
{"not", NOT},
{"member", MEMBER},
{"memq", MEMQ},
{"neq", NEQ},
{"eq", EQ},
{"geq", GEQ},
{"leq", LEQ},
{"freeof", FREEOF},
{"symbolic", SYMBOLIC},
{"algebraic", ALGEBRAIC},
{"expr", EXPR},
{"macro", MACRO},
{"smacro", SMACRO},
{"procedure", PROCEDURE},
{"for", FOR},
{"step", STEP},
{"until", UNTIL},
{"each", EACH},
{"foreach", FOREACH},
{"in", IN},
{"on", ON},
{"do", DO},
{"collect", COLLECT},
{"sum", SUM},
{"if", IF},
{"then", THEN},
{"else", ELSE},
{"repeat", REPEAT},
{"while", WHILE},
{"begin", BEGIN},
{"end", END},
{":lsect", LSECT},
{":rsect", RSECT},
{"go", GO},
{"to", TO},
{"goto", GOTO},
{"scalar", SCALAR},
{"integer", INTEGER},
{"lambda", LAMBDA},
{":symbol", SYMBOL},
{":number", NUMBER},
{":string", STRING},
{":list", LIST},
{"return", RETURN},
{"where", WHERE},
{"rlistat", RLISTAT},
{"endstat", ENDSTAT},
{"!#if", HASHIF},
{"!#else", HASHELSE},
{"!#elif", HASHELIF},
{"!#endif", HASHENDIF},
{NULL, 0}
};
int skipcomment()
{
if (ch == '%')
{ while (ch != '\n' && ch != -1) nextch();
return 1;
}
else return 0;
}
static intptr_t onechar(int c)
{
char b[4];
b[0] = c;
b[1] = 0;
return find_symbol(b);
}
intptr_t lisp_token()
{
char buffer[1000];
int bp = 0, num = 0;
intptr_t r;
while (isspace(ch) || skipcomment()) nextch();
num = isdigit(ch);
while (isalpha(ch) || isdigit(ch) || ch=='_' || ch == '!' ||
(num && ch == '.'))
{ buffer[bp++] = ch;
if (ch == '!')
{ buffer[bp++] = nextch();
}
nextch();
}
buffer[bp] = 0;
if (bp != 0)
{ yylval.LO = find_symbol((char *)buffer);
return num ? '0': 'a';
}
if (ch == '"')
{ for (;;)
{ buffer[bp++] = ch;
while (nextch() != '"' && ch != '\n' && ch != EOF)
buffer[bp++] = ch;
buffer[bp++] = ch;
if (nextch() != '"') break;
}
buffer[bp] = 0;
yylval.LO = find_symbol((char *)buffer);
return '"';
}
if (ch == '\'' || ch == '(' || ch == ')' || ch == '.')
{ r = ch;
nextch();
return r;
}
r = ch;
nextch();
return onechar(r);
}
static intptr_t read_tail();
/*
* L -> atom
* L -> ' L
* L -> ( T
* L -> . error
* L -> ) error
*
* T -> )
* T -> . L )
* T -> L T
*
*/
static intptr_t read_list(intptr_t r)
{
switch (r)
{
case '(': return read_tail();
case '.':
case ')': return C_nil; /* errors! */
case '\'':
return list2(find_symbol("quote"), read_list(lisp_token()));
default:
return yylval.LO;
}
}
intptr_t read_tail()
{
intptr_t r;
switch (r = lisp_token())
{
case ')': return C_nil;
case '.': r = read_list(lisp_token());
if (lisp_token() != ')') fprintf(stderr, "\nBad syntax after '.'\n");
return r;
case '\'':
r = list2(find_symbol("quote"), read_list(lisp_token()));
return cons(r, read_tail());
case '(': r = read_list(r);
return cons(r, read_tail());
default: r = yylval.LO;
return cons(r, read_tail());
}
}
static int skipping = 0;
static intptr_t genuine_yylex();
static int evaluates_to_true(intptr_t r)
{
intptr_t fn, arg;
char *s, *v;
if (r == C_nil) return 0;
else if (atom(r))
{ s = (char *)r;
v = lookup_name(s-1);
if (v == NULL) return 0;
else return 1;
}
fn = qcar(r);
r = qcdr(r);
if (fn == C_nil || !atom(fn)) return 0;
s = (char *)fn;
if (strcmp(s-1, "and") == 0)
{ while (r != C_nil && !atom(r))
{ arg = qcar(r);
r = qcdr(r);
if (!evaluates_to_true(arg)) return 0;
}
return 1;
}
else if (strcmp(s-1, "or") == 0)
{ while (r != C_nil && !atom(r))
{ arg = qcar(r);
r = qcdr(r);
if (evaluates_to_true(arg)) return 1;
}
return 0;
}
else if (strcmp(s-1, "not") == 0)
return !evaluates_to_true(qcar(r));
else return 0; /* junk treated as false! */
}
static void skip_tokens()
{
intptr_t r;
skipping = 1;
for (;;)
{ r = genuine_yylex();
switch (r)
{
case HASHIF:
skipping++;
continue;
case HASHELSE:
if (skipping == 1)
{ skipping = 0;
return;
}
else continue;
case HASHELIF:
if (skipping == 1)
{ skipping = 0;
r = read_list(lisp_token());
if (evaluates_to_true(r)) return;
skipping = 1;
continue;
}
else continue;
case HASHENDIF:
skipping--;
if (skipping == 0) return;
else continue;
default:continue;
}
}
}
static intptr_t genuine_yylex()
{
char buffer[1000];
int bp, num;
intptr_t r;
restart_lex:
bp = 0;
num = 0;
while (isspace(ch) || skipcomment()) nextch();
if (ch == -1)
{ if (skipping)
{ printf("\n+++ EOF while within !#if\n");
exit(1);
}
return ENDFILE;
}
num = isdigit(ch);
while (isalpha(ch) || isdigit(ch) || ch=='_' || ch == '!' ||
(num && ch == '.'))
{ buffer[bp++] = ch;
if (ch == '!')
{ buffer[bp++] = nextch();
}
nextch();
}
buffer[bp] = 0;
if (bp != 0)
{ int k;
for (k=0;;k++)
{ char *n = operators[k].name;
int v = operators[k].code;
if (n == NULL) break;
if (v < 0) continue;
if (strcmp(n, buffer) == 0)
{
switch (v)
{
case HASHIF:
if (skipping != 0) return v;
r = read_list(lisp_token());
if (!evaluates_to_true(r)) skip_tokens();
goto restart_lex;
case HASHELSE:
case HASHELIF:
if (skipping != 0) return v;
skip_tokens();
goto restart_lex;
case HASHENDIF:
if (skipping != 0) return v;
else goto restart_lex; /* Ignore it! */
default:break;
}
return v;
}
}
yylval.LO = find_symbol((char *)buffer);
return num ? NUMBER : SYMBOL;
}
if (ch == '"')
{ for (;;)
{ buffer[bp++] = ch;
while (nextch() != '"' && ch != EOF && ch != '\n')
buffer[bp++] = ch;
buffer[bp++] = ch;
if (nextch() != '"') break;
}
buffer[bp] = 0;
yylval.LO = find_symbol((char *)buffer);
return STRING;
}
if (ch == '\'')
{ nextch();
r = read_list(lisp_token());
yylval.LO = list2(find_symbol("quote"), r);
return LIST;
}
r = ch;
nextch();
if (r == ':' && ch == '=') { nextch(); r = SETQ; }
else if (r == '<' && ch == '=') { nextch(); r = LEQ; }
else if (r == '>' && ch == '=') { nextch(); r = GEQ; }
else if (r == '<' && ch == '<') { nextch(); r = LSECT; }
else if (r == '>' && ch == '>') { nextch(); r = RSECT; }
return r;
}
static intptr_t yylex()
{
return genuine_yylex();
}
/* end of file */