Author: kjs
Date: Wed Apr 4 13:08:48 2007
New Revision: 17979
Modified:
trunk/compilers/pirc/src/pirparser.c
Log:
compilers/pirc:
* fixed long invocation syntax
* add some comments here and there, changed syntax_error() to bail out after
first error,resulting in much better error report.
Modified: trunk/compilers/pirc/src/pirparser.c
==============================================================================
--- trunk/compilers/pirc/src/pirparser.c (original)
+++ trunk/compilers/pirc/src/pirparser.c Wed Apr 4 13:08:48 2007
@@ -265,23 +265,35 @@
}
else {
if (p->curtoken == T_EOF) { /* no characters have been read, so
nothing to display */
- syntax_error(p, 3 , "expected ", find_keyword(expected), " but got
end of file");
+ syntax_error(p, 3 , "expected '", find_keyword(expected), "' but
got end of file");
exit_parser(p); /* no use to continue when having read end of
file */
}
else { /* 'normal' error; not end of file yet */
- syntax_error(p, 4, "expected ", find_keyword(expected), " but got:
", find_keyword(p->curtoken));
+ syntax_error(p, 4, "expected '", find_keyword(expected), "' but
got: ", find_keyword(p->curtoken));
- /* Try to reduce errors; skip tokens up to ".end" and
- * try to continue with the next subroutine, if any
+ /* XXX
+ * exiting here right away gives a much nicer error report.
Suggestion for later: try to read tokens
+ * up to end of line where syntax_error() is called, at >that<
point, we know what the next token should
+ * be, probably making it possible to continue without too many
errors.
+ */
+ exit_parser(p);
+
+ /* Try to reduce errors; skip tokens up to the end of line and
+ * try to continue with the next line, if any
*/
+
+ /*
do {
next(p);
}
- while (p->curtoken != T_END && p->curtoken != T_EOF);
+ while (p->curtoken != T_NEWLINE && p->curtoken != T_EOF);
+ */
/* loop broke, see what happened: */
- if (p->curtoken == T_END) next(p);
- else exit_parser(p); /* we got T_EOF; clean up and go home */
+ /*
+ if (p->curtoken == T_NEWLINE) next(p);
+ else exit_parser(p); */ /* we got T_EOF; clean up and go home */
+
}
}
@@ -334,11 +346,9 @@
case T_PASM_IREG: case T_IREG:
case T_PASM_SREG: case T_SREG:
case T_MACRO_IDENT:
- exprtok = p->curtoken;
-
+ exprtok = p->curtoken; /* store current token type to return */
/* emit the expression */
emit_expr(p, get_current_token(p->lexer));
-
next(p);
break;
default:
@@ -361,12 +371,11 @@
*/
static void
string_value(parser_state *p) {
- /* also allow string registers */
+ /* also allow string registers, but /no/ identifiers! */
switch (p->curtoken) {
case T_SREG:
case T_PASM_SREG:
case T_STRING_CONSTANT:
- /* case T_IDENTIFIER: string variable? */
next(p);
break;
default:
@@ -797,7 +806,11 @@
=item *
- return_statement -> '.return' ( arguments | target ['->' method] arguments |
methodcall ) '\n'
+ return_statement -> '.return' ( arguments
+ | target ['->' method] arguments
+ | methodcall
+ )
+ '\n'
=cut
@@ -887,7 +900,9 @@
=item *
- local_id_list -> IDENTIFIER [':unique_reg'] { ',' IDENTIFIER [':unique_reg']
}
+ local_id_list -> local_id { ',' local_id }
+
+ local_id -> IDENTIFIER [':unique_reg']
=cut
@@ -897,7 +912,10 @@
emit_expr(p, get_current_token(p->lexer));
match(p, T_IDENTIFIER);
- if (p->curtoken == T_UNIQUE_REG_FLAG) next(p);
+ /* process the flag, if any */
+ if (p->curtoken == T_UNIQUE_REG_FLAG) {
+ next(p);
+ }
while (p->curtoken == T_COMMA) {
next(p); /* skip comma */
@@ -995,7 +1013,7 @@
conditional_expression -> expression [cond_op expression]
- cond_op -> '>' | '>=' | '<' | '<=' | '==' | '!='
+ cond_op -> '>' | '>=' | '<' | '<=' | '==' | '!='
=cut
@@ -1240,9 +1258,36 @@
=item *
+ invokable -> IDENTIFIER | PREG
+
+=cut
+
+*/
+static void
+invocant(parser_state *p) {
+ switch (p->curtoken) {
+ case T_IDENTIFIER:
+ case T_PREG:
+ case T_PASM_PREG:
+ emit_invokable(p, get_current_token(p->lexer));
+ next(p);
+ break;
+ default:
+ syntax_error(p, 1, "invokable object expected");
+ break;
+ }
+}
+
+/*
+
+=item *
+
long-invocation -> '.pcc_begin' '\n'
{ '.arg' expression arg_flags }
- ('.pcc_call'|'.nci_call'|'.meth_call')
+ ( '.pcc_call'|'.nci_call') invocant '\n'
+ | '.invocant' invocant '\n'
+ '.meth_call' method '\n'
+ )
{ (local_declaration| '.result' target '\n') }
'.pcc_end' '\n'
@@ -1255,12 +1300,12 @@
emit_invocation_start(p);
- match(p, T_PCC_BEGIN); /* '.pcc_begin '\n' ... */
+ match(p, T_PCC_BEGIN); /* '.pcc_begin '\n' */
match(p, T_NEWLINE);
/* arguments */
emit_args_start(p);
- while (p->curtoken == T_ARG) { /* ... { '.arg' expr [flag] '\n' } ... */
+ while (p->curtoken == T_ARG) { /* { '.arg' expr [flag] '\n' } */
next(p);
expression(p);
arg_flags(p);
@@ -1270,18 +1315,18 @@
/* the invocant and/or sub to be called */
switch (p->curtoken) {
- case T_PCC_CALL: /* ... '.pcc_call' target '\n' ... */
- case T_NCI_CALL: /* ... '.nci_call' target '\n' ... */
+ case T_PCC_CALL: /* '.pcc_call' invocant '\n' */
+ case T_NCI_CALL: /* '.nci_call' invocant '\n' */
next(p);
- target(p);
+ invocant(p);
match(p, T_NEWLINE);
break;
- case T_INVOCANT: /* '.invocant' target '\n' */
+ case T_INVOCANT: /* '.invocant' invocant '\n' */
next(p);
- target(p);
+ invocant(p);
match(p, T_NEWLINE);
- match(p, T_METH_CALL); /* .meth_call target '\n' */
- target(p);
+ match(p, T_METH_CALL); /* .meth_call method '\n' */
+ method(p);
match(p, T_NEWLINE);
break;
default:
@@ -1468,7 +1513,7 @@
=item *
- multi-result-invocation -> target_list '=' (invokable arguments |
methodcall)) '\n'
+ multi-result-invocation -> target_list '=' (invokable arguments |
methodcall) '\n'
invokable -> IDENTIFIER | PREG | STRINGC
@@ -1851,13 +1896,13 @@
break;
case T_OUTER_FLAG:
case T_VTABLE_FLAG: {
- emit_sub_flag(p, p->curtoken);
+ emit_sub_flag(p, p->curtoken); /* emit current flag */
next(p);
- emit_list_start(p);
+ emit_list_start(p); /* start a list of flag arguments --
needed? only 1 arg.. */
match(p, T_LPAREN);
emit_expr(p, get_current_token(p->lexer));
match(p, T_STRING_CONSTANT);
- emit_list_end(p);
+ emit_list_end(p); /* close list of arguments -- needed? */
match(p, T_RPAREN);
break;
}
