Factor the generation of the (integral) tables bw yacc.c and lalr1.cc.

[bison.git] / data / bison.m4

diff --git a/data/bison.m4 b/data/bison.m4
index 6e1922b1ab9cf831dcfdbe10a7dee8df1fa20f50..efcf2bd0bca224ac3eeff9d108d9ec817805192f 100644 (file)
--- a/data/bison.m4
+++ b/data/bison.m4
@@ -1,7 +1,8 @@
                                                             -*- Autoconf -*-
 
 # Language-independent M4 Macros for Bison.
-# Copyright (C) 2002, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
+# Copyright (C) 2002, 2004, 2005, 2006, 2007, 2008 Free Software Foundation,
+# Inc.
 
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -21,14 +22,17 @@
 ## Identification.  ##
 ## ---------------- ##
 
-# b4_copyright(TITLE, YEARS)
-# --------------------------
+# b4_copyright(TITLE, [YEARS])
+# ----------------------------
+# If YEARS are not defined, use b4_copyright_years.
 m4_define([b4_copyright],
 [b4_comment([A Bison parser, made by GNU Bison b4_version.])
 
 b4_comment([$1
 
-m4_text_wrap([Copyright (C) $2 Free Software Foundation, Inc.], [   ])
+]m4_dquote(m4_text_wrap([Copyright (C)
+]m4_ifval([$2], [[$2]], [m4_defn([b4_copyright_years])])[
+Free Software Foundation, Inc.]))[
 
 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
@@ -208,6 +212,88 @@ m4_define([b4_ints_in],
 [m4_eval([$3 <= $1 && $1 <= $4 && $3 <= $2 && $2 <= $4])])
 
 
+# b4_subtract(LHS, RHS)
+# ---------------------
+# Evaluate LHS - RHS if they are integer literals, otherwise expand
+# to (LHS) - (RHS).
+m4_define([b4_subtract],
+[m4_bmatch([$1$2], [^[0123456789]*$],
+           [m4_eval([$1 - $2])],
+           [($1) - ($2)])])
+
+# b4_args(ARG1, ...)
+# _b4_args(ARG1, ...)
+# -------------------
+# Join with comma, skipping empty arguments.
+# b4_args calls itself recursively until it sees the first non-empty
+# argument, then calls _b4_args which prepends each non-empty argument
+# with a comma.
+m4_define([b4_args],
+[m4_if([$#$1],
+       [1], [],
+       [m4_ifval([$1],
+                 [$1[]_$0(m4_shift($@))],
+                 [$0(m4_shift($@))])])])
+
+# _b4_args(ARGS1, ...)
+# --------------------
+m4_define([_b4_args],
+[m4_if([$#$1],
+       [1], [],
+       [m4_ifval([$1], [, $1])[]$0(m4_shift($@))])])
+
+
+
+
+# b4_tables_map(MACRO)
+# --------------------
+# Map MACRO on all the integral tables.  MACRO is expected to have
+# the signature MACRO(TABLE-NAME, CONTENT, COMMENT).
+m4_define([b4_tables_map],
+[$1([pact], [b4_pact],
+    [[YYPACT[STATE-NUM] -- Index in YYTABLE of the portion describing
+STATE-NUM.]])
+
+$1([defact], [b4_defact],
+   [[YYDEFACT[S] -- default rule to reduce with in state S when YYTABLE
+does not specify something else to do.  Zero means the default is an
+error.]])
+
+$1([pgoto], [b4_pgoto], [[YYPGOTO[NTERM-NUM].]])
+
+$1([defgoto], [b4_defgoto], [[YYDEFGOTO[NTERM-NUM].]])
+
+$1([table], [b4_table],
+   [[YYTABLE[YYPACT[STATE-NUM]].  What to do in state STATE-NUM.  If
+positive, shift that token.  If negative, reduce the rule which
+number is the opposite.  If zero, do what YYDEFACT says.
+If YYTABLE_NINF, syntax error.]])
+
+$1([check], [b4_check])
+
+$1([stos], [b4_stos],
+   [[STOS_[STATE-NUM] -- The (internal number of the) accessing
+symbol of state STATE-NUM.]])
+
+$1([r1], [b4_r1],
+   [[YYR1[YYN] -- Symbol number of symbol that rule YYN derives.]])
+
+$1([r2], [b4_r2],
+   [[YYR2[YYN] -- Number of symbols composing right hand side of rule YYN.]])
+])
+
+
+# b4_tables_declare
+# b4_tables_define
+# -----------------
+# Define/declare the (deterministic) parser tables.
+m4_define([b4_tables_declare],
+[b4_tables_map([b4_table_declare])])
+
+m4_define([b4_tables_define],
+[b4_tables_map([b4_table_define])])
+
+
 
 ## ------------------ ##
 ## Decoding options.  ##
@@ -253,11 +339,6 @@ b4_define_flag_if([nondeterministic])      # Whether conflicts should be handled.
 b4_define_flag_if([yacc])              # Whether POSIX Yacc is emulated.
 
 
-## ------------------------- ##
-## Assigning token numbers.  ##
-## ------------------------- ##
-
-
 ## ----------- ##
 ## Synclines.  ##
 ## ----------- ##
@@ -521,7 +602,7 @@ m4_define([b4_percent_code_get],
 m4_ifval([$1], [m4_define([b4_percent_code_bison_qualifiers(]$1[)])])dnl
 m4_ifdef(b4_macro_name,
 [b4_comment([m4_if([$#], [0], [[Unqualified %code]],
-                   [[%code "]$1["]])[ blocks.]])
+                   [["%code ]$1["]])[ blocks.]])
 b4_user_code([m4_indir(b4_macro_name)])
 ])dnl
 m4_popdef([b4_macro_name])])
@@ -538,6 +619,13 @@ m4_define([b4_percent_code_ifdef],
          [$3])])
 
 
+# Default values for %define.
+# ---------------------------
+# If the %token.prefix, it is empty.
+m4_percent_define_default([[token.prefix]], [[]])
+
+
+
 ## ----------------------------------------------------------- ##
 ## After processing the skeletons, check that all the user's   ##
 ## %define variables and %code qualifiers were used by Bison.  ##
@@ -549,7 +637,7 @@ m4_define([b4_check_user_names_wrap],
                                [b4_percent_]$1[_user_]$2[s],
                                [[b4_percent_]$1[_bison_]$2[s]])])])
 
-m4_wrap([
+m4_wrap_lifo([
 b4_check_user_names_wrap([[define]], [[variable]])
 b4_check_user_names_wrap([[code]], [[qualifier]])
 ])