+
+
+## ----------------------- ##
+## @$ implies %locations. ##
+## ----------------------- ##
+
+# Bison once forgot to check for @$ in actions other than semantic actions.
+
+# AT_CHECK_ACTION_LOCATIONS(ACTION-DIRECTIVE)
+# -------------------------------------------
+m4_define([AT_CHECK_ACTION_LOCATIONS],
+[AT_SETUP([[@$ in ]$1[ implies %locations]])
+AT_BISON_OPTION_PUSHDEFS([%debug])
+AT_DATA_GRAMMAR([[input.y]],
+[[%code {
+ #include <stdio.h>
+]AT_YYERROR_DECLARE[
+]AT_YYLEX_DECLARE[
+}
+
+%debug
+
+]$1[ {
+ fprintf (stderr, "%d\n", @$.first_line);
+} ]m4_if($1, [%initial-action], [], [[start]])[
+
+%%
+
+start: ;
+
+%%
+
+static int
+yylex (void)
+{
+ return 0;
+}
+
+]AT_YYERROR_DEFINE[
+]AT_MAIN_DEFINE[
+]])
+
+AT_BISON_CHECK([[-o input.c input.y]])
+AT_COMPILE([[input]])
+AT_BISON_OPTION_POPDEFS
+AT_CLEANUP])
+
+AT_CHECK_ACTION_LOCATIONS([[%initial-action]])
+AT_CHECK_ACTION_LOCATIONS([[%destructor]])
+AT_CHECK_ACTION_LOCATIONS([[%printer]])
+
+
+## ------------------------- ##
+## Qualified $$ in actions. ##
+## ------------------------- ##
+
+# Check that we can use qualified $$ (v.g., $<type>$) not only in rule
+# actions, but also where $$ is valid: %destructor/%printer and
+# %initial-action.
+#
+# FIXME: Not actually checking %destructor, but it's the same code as
+# %printer...
+#
+# To do that, use a semantic value that has two fields (sem_type),
+# declare symbols to have only one of these types (INT, float), and
+# use $<type>$ to get the other one. Including for symbols that are
+# not typed (UNTYPED).
+
+m4_pushdef([AT_TEST],
+[AT_SETUP([[Qualified $$ in actions: $1]])
+
+AT_BISON_OPTION_PUSHDEFS([%skeleton "$1" %debug])
+
+AT_DATA_GRAMMAR([[input.y]],
+[[%skeleton "$1"
+%debug
+%code requires
+{
+ typedef struct sem_type
+ {
+ int ival;
+ float fval;
+ } sem_type;
+
+# define YYSTYPE sem_type
+
+]AT_SKEL_CC_IF([[
+# include <iostream>
+ static void
+ report (std::ostream& yyo, int ival, float fval)
+ {
+ yyo << "ival: " << ival << ", fval: " << fval;
+ }
+]], [[
+# include <stdio.h>
+ static void
+ report (FILE* yyo, int ival, float fval)
+ {
+ fprintf (yyo, "ival: %d, fval: %1.1f", ival, fval);
+ }
+]])[
+}
+
+%code
+{
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
+}
+
+%token UNTYPED
+%token <ival> INT
+%type <fval> float
+%printer { report (yyo, $$, $<fval>$); } <ival>;
+%printer { report (yyo, $<ival>$, $$ ); } <fval>;
+%printer { report (yyo, $<ival>$, $<fval>$); } <>;
+
+%initial-action
+{
+ $<ival>$ = 42;
+ $<fval>$ = 4.2;
+}
+
+%%
+float: UNTYPED INT
+{
+ $$ = $<fval>1 + $<fval>2;
+ $<ival>$ = $<ival>1 + $][2;
+};
+%%
+]AT_YYERROR_DEFINE[
+]AT_YYLEX_DEFINE(AT_SKEL_CC_IF([[{yy::parser::token::UNTYPED,
+ yy::parser::token::INT,
+ EOF}]],
+ [[{UNTYPED, INT, EOF}]]),
+ [AT_VAL.ival = toknum * 10; AT_VAL.fval = toknum / 10.0;])[
+]AT_MAIN_DEFINE[
+]])
+
+AT_FULL_COMPILE([[input]])
+AT_PARSER_CHECK([./input --debug], 0, [], [stderr])
+# Don't be too picky on the traces, GLR is not exactly the same. Keep
+# only the lines from the printer.
+AT_CHECK([[sed -ne '/ival:/p' stderr]], 0,
+[[Reading a token: Next token is token UNTYPED (ival: 10, fval: 0.1)
+Shifting token UNTYPED (ival: 10, fval: 0.1)
+Reading a token: Next token is token INT (ival: 20, fval: 0.2)
+Shifting token INT (ival: 20, fval: 0.2)
+ $][1 = token UNTYPED (ival: 10, fval: 0.1)
+ $][2 = token INT (ival: 20, fval: 0.2)
+-> $$ = nterm float (ival: 30, fval: 0.3)
+Cleanup: popping nterm float (ival: 30, fval: 0.3)
+]])
+
+AT_BISON_OPTION_POPDEFS
+
+AT_CLEANUP
+])
+
+AT_TEST([yacc.c])
+AT_TEST([glr.c])
+AT_TEST([lalr1.cc])
+AT_TEST([glr.cc])
+
+m4_popdef([AT_TEST])
+
+## -------------------------------------------------- ##
+## Destroying lookahead assigned by semantic action. ##
+## -------------------------------------------------- ##
+
+AT_SETUP([[Destroying lookahead assigned by semantic action]])
+
+AT_BISON_OPTION_PUSHDEFS
+AT_DATA_GRAMMAR([input.y],
+[[
+%code {
+ #include <assert.h>
+ #include <stdio.h>
+]AT_YYERROR_DECLARE[
+]AT_YYLEX_DECLARE[
+ #define USE(Var)
+}
+
+%destructor { fprintf (stderr, "'a' destructor\n"); } 'a'
+%destructor { fprintf (stderr, "'b' destructor\n"); } 'b'
+
+%%
+
+// In a previous version of Bison, yychar assigned by the semantic
+// action below was not translated into yytoken before the lookahead was
+// discarded and thus before its destructor (selected according to
+// yytoken) was called in order to return from yyparse. This would
+// happen even if YYACCEPT was performed in a later semantic action as
+// long as only consistent states with default reductions were visited
+// in between. However, we leave YYACCEPT in the same semantic action
+// for this test in order to show that skeletons cannot simply translate
+// immediately after every semantic action because a semantic action
+// that has set yychar might not always return normally. Instead,
+// skeletons must translate before every use of yytoken.
+start: 'a' accept { USE($1); } ;
+accept: %empty {
+ assert (yychar == YYEMPTY);
+ yychar = 'b';
+ YYACCEPT;
+} ;
+
+%%
+]AT_YYERROR_DEFINE[
+]AT_YYLEX_DEFINE(["a"])[
+]AT_MAIN_DEFINE[
+]])
+AT_BISON_OPTION_POPDEFS
+AT_BISON_CHECK([[-o input.c input.y]])
+AT_COMPILE([[input]])
+AT_PARSER_CHECK([[./input]], [[0]], [],
+[['b' destructor
+'a' destructor
+]])
+
+AT_CLEANUP
+
+## ---------- ##
+## YYBACKUP. ##
+## ---------- ##
+
+AT_SETUP([[YYBACKUP]])
+
+AT_BISON_OPTION_PUSHDEFS([%pure-parser %debug])
+
+AT_DATA_GRAMMAR([input.y],
+[[
+%error-verbose
+%debug
+%pure-parser
+%code {
+# include <stdio.h>
+# include <stdlib.h>
+# include <assert.h>
+
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
+}
+%%
+input:
+ exp exp {}
+;
+
+exp:
+ 'a' { printf ("a: %d\n", $1); }
+| 'b' { YYBACKUP('a', 123); }
+| 'c' 'd' { YYBACKUP('a', 456); }
+;
+
+%%
+]AT_YYERROR_DEFINE[
+]AT_YYLEX_DEFINE(["bcd"], [*lvalp = (toknum + 1) * 10])[
+]AT_MAIN_DEFINE[
+]])
+AT_BISON_OPTION_POPDEFS
+
+AT_BISON_CHECK([[-o input.c input.y]])
+AT_COMPILE([[input]])
+AT_PARSER_CHECK([[./input]], [[0]],
+[[a: 123
+a: 456
+]])
+
+AT_CLEANUP
projects / bison.git / blobdiff