Parameterize the extraction of semantic values.

To make future changes easier, no longer rely on ".TYPE" being the
way to get a semantic value.

	* data/c.m4 (b4_symbol_value): New.
	Use it.
	* data/c++.m4, data/yacc.c: Use it.
	* data/glr.c: Use b4_symbol_value.
	(b4_rhs_data): New.
	Use it.
This commit is contained in:
Akim Demaille
2008-10-21 17:20:22 -05:00
parent 91ba8a55b1
commit 1fa5d8bbf9
5 changed files with 45 additions and 8 deletions

View File

@@ -102,7 +102,7 @@ m4_map_sep([ b4_token_enum], [,
# --------------------
# Expansion of $<TYPE>$.
m4_define([b4_lhs_value],
[(yyval[]m4_ifval([$1], [.$1]))])
[b4_symbol_value([yyval], [$1])])
# b4_rhs_value(RULE-LENGTH, NUM, [TYPE])
@@ -110,7 +110,8 @@ m4_define([b4_lhs_value],
# Expansion of $<TYPE>NUM, where the current rule has RULE-LENGTH
# symbols on RHS.
m4_define([b4_rhs_value],
[(yysemantic_stack_@{($1) - ($2)@}m4_ifval([$3], [.$3]))])
[b4_symbol_value([yysemantic_stack_@{($1) - ($2)@}], [$3])])
# b4_lhs_location()
# -----------------

View File

@@ -205,6 +205,21 @@ m4_define([b4_token_enums_defines],
])
## ----------------- ##
## Semantic Values. ##
## ----------------- ##
# b4_symbol_value(VAL, [TYPE])
# ----------------------------
# Given a semantic value VAL ($$, $1 etc.), extract its value of type
# TYPE if TYPE is given, otherwise just return VAL. The result can be
# used safetly, it is put in parens to avoid nasty precedence issues.
# TYPE is *not* put in braces, provide some if needed.
m4_define([b4_symbol_value],
[($1[]m4_ifval([$2], [.$2]))])
## --------------------------------------------- ##
## Defining C functions in both K&R and ANSI-C. ##
@@ -360,7 +375,7 @@ $2
# -------------------------------------------------
m4_define([b4_symbol_actions],
[m4_pushdef([b4_dollar_dollar],
[m4_ifval([$6], [(yyvaluep->$6)], [(*yyvaluep)])])dnl
[b4_symbol_value([(*yyvaluep)], [$6])])dnl
m4_pushdef([b4_at_dollar], [(*yylocationp)])dnl
case $4: /* $3 */
b4_syncline([$2], [$1])

View File

@@ -109,7 +109,15 @@ m4_define([b4_pure_formals],
# --------------------
# Expansion of $<TYPE>$.
m4_define([b4_lhs_value],
[((*yyvalp)[]m4_ifval([$1], [.$1]))])
[b4_symbol_value([(*yyvalp)], [$1])])
# b4_rhs_data(RULE-LENGTH, NUM)
# -----------------------------
# Expand to the semantic stack place that contains value and location
# of symbol number NUM in a rule of length RULE-LENGTH.
m4_define([b4_rhs_data],
[((yyGLRStackItem const *)yyvsp)@{YYFILL (($2) - ($1))@}.yystate])
# b4_rhs_value(RULE-LENGTH, NUM, [TYPE])
@@ -117,7 +125,7 @@ m4_define([b4_lhs_value],
# Expansion of $<TYPE>NUM, where the current rule has RULE-LENGTH
# symbols on RHS.
m4_define([b4_rhs_value],
[(((yyGLRStackItem const *)yyvsp)@{YYFILL (($2) - ($1))@}.yystate.yysemantics.yysval[]m4_ifval([$3], [.$3]))])
[b4_symbol_value([b4_rhs_data([$1], [$2]).yysemantics.yysval], [$3])])
@@ -137,7 +145,7 @@ m4_define([b4_lhs_location],
# Expansion of @NUM, where the current rule has RULE-LENGTH symbols
# on RHS.
m4_define([b4_rhs_location],
[(((yyGLRStackItem const *)yyvsp)@{YYFILL (($2) - ($1))@}.yystate.yyloc)])
[(b4_rhs_data([$1], [$2]).yyloc)])

View File

@@ -114,7 +114,7 @@ m4_define([b4_int_type],
# --------------------
# Expansion of $<TYPE>$.
m4_define([b4_lhs_value],
[(yyval[]m4_ifval([$1], [.$1]))])
[b4_symbol_value(yyval, [$1])])
# b4_rhs_value(RULE-LENGTH, NUM, [TYPE])
@@ -122,7 +122,7 @@ m4_define([b4_lhs_value],
# Expansion of $<TYPE>NUM, where the current rule has RULE-LENGTH
# symbols on RHS.
m4_define([b4_rhs_value],
[(yyvsp@{($2) - ($1)@}m4_ifval([$3], [.$3]))])
[b4_symbol_value([yyvsp@{($2) - ($1)@}], [$3])])