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c, c++: also define YYEMPTY in yytoken_kind_t

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I have been hesitating a lot before doing it ---after all the user
must not use this kind, so what's the point of showing it in
yytoken_kind_t.  And eventually I chose to play it safe with the
typing system and make it possible to use yytoken_kind_t for all the
tokens, even the "empty token".

* data/skeletons/c.m4: Give an id and a tag to YYEMPTY.
(b4_token_enums): Define YYEMPTY.
* data/skeletons/c++.m4 (b4_token_enums): Define YYEMPTY.
* data/skeletons/glr.c, data/skeletons/glr.cc, data/skeletons/yacc.c:
(YYEMPTY): Remove.
Use b4_symbol(-2, id) instead.
This commit is contained in:
Akim Demaille
2020-04-13 08:05:09 +02:00
parent 5e2e9af56d
commit 64aec0a8d8
5 changed files with 34 additions and 30 deletions
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30
data/skeletons/glr.c
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@@ -429,8 +429,6 @@ int yychar;])[
enum { YYENOMEM = -2 };
static const int YYEMPTY = -2;
typedef enum { yyok, yyaccept, yyabort, yyerr } YYRESULTTAG;
#define YYCHK(YYE) \
@@ -525,7 +523,7 @@ struct yyGLRStateSet {
/** During nondeterministic operation, yylookaheadNeeds tracks which
* stacks have actually needed the current lookahead. During deterministic
* operation, yylookaheadNeeds[0] is not maintained since it would merely
* duplicate yychar != YYEMPTY. */
* duplicate yychar != ]b4_symbol(-2, id)[. */
yybool* yylookaheadNeeds;
ptrdiff_t yysize;
ptrdiff_t yycapacity;
@@ -809,7 +807,7 @@ yygetToken (int *yycharp][]b4_pure_if([, yyGLRStack* yystackp])[]b4_user_formals
{
yysymbol_kind_t yytoken;
]b4_parse_param_use()dnl
[ if (*yycharp == YYEMPTY)
[ if (*yycharp == ]b4_symbol(-2, id)[)
{
YY_DPRINTF ((stderr, "Reading a token\n"));]b4_glr_cc_if([[
#if YY_EXCEPTIONS
@@ -887,7 +885,7 @@ yyuserAction (yyRuleNum yyn, int yyrhslen, yyGLRStackItem* yyvsp,
# undef YYRECOVERING
# define YYRECOVERING() (yystackp->yyerrState != 0)
# undef yyclearin
# define yyclearin (yychar = YYEMPTY)
# define yyclearin (yychar = ]b4_symbol(-2, id)[)
# undef YYFILL
# define YYFILL(N) yyfill (yyvsp, &yylow, (N), yynormal)
# undef YYBACKUP
@@ -1113,7 +1111,7 @@ yyaddDeferredAction (yyGLRStack* yystackp, ptrdiff_t yyk, yyGLRState* yystate,
yynewOption->yyloc = yylloc;])[
}
else
yynewOption->yyrawchar = YYEMPTY;
yynewOption->yyrawchar = ]b4_symbol(-2, id)[;
yynewOption->yynext = yystate->yysemantics.yyfirstVal;
yystate->yysemantics.yyfirstVal = yynewOption;
@@ -2134,7 +2132,7 @@ static yysymbol_kind_t
yypcontext_token (const yyGLRStack *yystackp)
{
YYUSE (yystackp);
yysymbol_kind_t yytoken = yychar == YYEMPTY ? ]b4_symbol_prefix[YYEMPTY : YYTRANSLATE (yychar);
yysymbol_kind_t yytoken = yychar == ]b4_symbol(-2, id)[ ? ]b4_symbol_prefix[YYEMPTY : YYTRANSLATE (yychar);
return yytoken;
}
@@ -2153,7 +2151,7 @@ yypcontext_location (const yyGLRStack *yystackp)
yy_syntax_error_arguments (const yyGLRStack* yystackp,
yysymbol_kind_t yyarg[], int yyargn)
{
yysymbol_kind_t yytoken = yychar == YYEMPTY ? ]b4_symbol_prefix[YYEMPTY : YYTRANSLATE (yychar);
yysymbol_kind_t yytoken = yychar == ]b4_symbol(-2, id)[ ? ]b4_symbol_prefix[YYEMPTY : YYTRANSLATE (yychar);
/* Actual size of YYARG. */
int yycount = 0;
/* There are many possibilities here to consider:
@@ -2313,7 +2311,7 @@ yyrecoverSyntaxError (yyGLRStack* yystackp]b4_user_formals[)
int yyj;
if (yychar == ]b4_symbol(0, [id])[)
yyFail (yystackp][]b4_lpure_args[, YY_NULLPTR);
if (yychar != YYEMPTY)
if (yychar != ]b4_symbol(-2, id)[)
{]b4_locations_if([[
/* We throw away the lookahead, but the error range
of the shifted error token must take it into account. */
@@ -2325,7 +2323,7 @@ yyrecoverSyntaxError (yyGLRStack* yystackp]b4_user_formals[)
yytoken = YYTRANSLATE (yychar);
yydestruct ("Error: discarding",
yytoken, &yylval]b4_locuser_args([&yylloc])[);
yychar = YYEMPTY;
yychar = ]b4_symbol(-2, id)[;
}
yytoken = ]b4_yygetToken_call[;
yyj = yypact[yystackp->yytops.yystates[0]->yylrState];
@@ -2422,7 +2420,7 @@ yyparse (]m4_ifset([b4_parse_param], [b4_formals(b4_parse_param)], [void])[)
YY_DPRINTF ((stderr, "Starting parse\n"));
yychar = YYEMPTY;
yychar = ]b4_symbol(-2, id)[;
yylval = yyval_default;]b4_locations_if([
yylloc = yyloc_default;])[
]m4_ifdef([b4_initial_action], [
@@ -2475,7 +2473,7 @@ b4_dollar_popdef])[]dnl
if (yyisShiftAction (yyaction))
{
YY_SYMBOL_PRINT ("Shifting", yytoken, &yylval, &yylloc);
yychar = YYEMPTY;
yychar = ]b4_symbol(-2, id)[;
yyposn += 1;
yyglrShift (&yystack, 0, yyaction, yyposn, &yylval]b4_locations_if([, &yylloc])[);
if (0 < yystack.yyerrState)
@@ -2501,7 +2499,7 @@ b4_dollar_popdef])[]dnl
ptrdiff_t yys;
for (yys = 0; yys < yystack.yytops.yysize; yys += 1)
yystackp->yytops.yylookaheadNeeds[yys] = yychar != YYEMPTY;
yystackp->yytops.yylookaheadNeeds[yys] = yychar != ]b4_symbol(-2, id)[;
/* yyprocessOneStack returns one of three things:
@@ -2539,11 +2537,11 @@ b4_dollar_popdef])[]dnl
/* If any yyglrShift call fails, it will fail after shifting. Thus,
a copy of yylval will already be on stack 0 in the event of a
failure in the following loop. Thus, yychar is set to YYEMPTY
failure in the following loop. Thus, yychar is set to ]b4_symbol(-2, id)[
before the loop to make sure the user destructor for yylval isn't
called twice. */
yytoken_to_shift = YYTRANSLATE (yychar);
yychar = YYEMPTY;
yychar = ]b4_symbol(-2, id)[;
yyposn += 1;
for (yys = 0; yys < yystack.yytops.yysize; yys += 1)
{
@@ -2593,7 +2591,7 @@ b4_dollar_popdef])[]dnl
goto yyreturn;
yyreturn:
if (yychar != YYEMPTY)
if (yychar != ]b4_symbol(-2, id)[)
yydestruct ("Cleanup: discarding lookahead",
YYTRANSLATE (yychar), &yylval]b4_locuser_args([&yylloc])[);