This cleans up our previous fixes for a bug whereby Bison
discarded `.field' in `$-1.field'. The previous fixes were less
restrictive about where a dash could appear in an identifier, but
the restrictions were hard to explain. That bug was reported and
this final fix was originally suggested by Paul Hilfinger. This
also fixes a remaining bug reported by Paul Eggert whereby Bison
parses `%token ID -123' as `%token ID - 123' and handles `-' as an
identifier. Now, `-' cannot be an identifier. Discussed in
threads beginning at
<http://lists.gnu.org/archive/html/bug-bison/2011-01/msg00000.html>,
<http://lists.gnu.org/archive/html/bug-bison/2011-01/msg00004.html>.
* NEWS (2.5): Update entry describing the dash extension to
grammar symbol names. Also, move that entry before the named
references entry because the latter mentions the former.
* doc/bison.texinfo (Symbol): Update documentation for symbol
names. As suggested by Paul Eggert, mention the effect of periods
and dashes on named references.
(Decl Summary): Update documentation for unquoted %define values,
which, as a side effect, can no longer start with dashes either.
* src/scan-code.l (id): Implement.
* src/scan-gram.l (id): Implement.
* tests/actions.at (Exotic Dollars): Extend test group to exercise
bug reported by Paul Hilfinger.
* tests/input.at (Symbols): Update test group, and extend to
exercise bug reported by Paul Eggert.
* tests/named-refs.at (Stray symbols in brackets): Update test
group.
($ or @ followed by . or -): Likewise.
* tests/regression.at (Invalid inputs): Likewise.
* doc/bison.texinfo (Mid-Rule Actions): Mention that periods and
dashes make symbol names less convenient for named references.
* src/scan-code.l:
(handle_action_dollar): New arg textlen. All callers changed.
(handle_action_at): Likewise. Also, args are pointers to const.
(ref_tail_fields): Remove; no longer used.
(letter): Now includes '-' and '.', since this is for Bison
identifiers.
(id): Now the simpler traditional defn, since letters now include
'-' and '.'.
(c_letter, c_id): New defns.
(ref): Use c_id for unbracketed IDs.
(<SC_RULE_ACTION>): Simplify, now that the distinction between
Bison and unbracketed IDs are now in the regular expressions.
(VARIANT_BAD_BRACKETING): Remove.
(VARIANT_NOT_VISIBLE_FROM_MIDRULE): Renumber.
(find_prefix_end): Remove, replacing with ....
(identifier_matches): New function.
(variant_add): Use it. Omit EXPLICIT_BRACKETING arg; no longer
needed. CP arg is pointer to constant. All callers changed.
(show_sub_messages): Remove args CP, EXPLICIT_BRACKETING, DOLLAR_OR_AT.
New arg TEXT. All callers changed. Do not worry about showing
trailing context.
(parse_ref): Args CP, RULE, TEXT are now pointers to const. New
arg TEXTLEN. Remove arg DOLLAR_OR_AT. All callers changed.
Simplify code now that the regular expressions capture the
restrictions.
* src/scan-gram.l (letter, id): Adjust to match scan-code.l.
* src/symlist.c (symbol_list_null): Arg is now pointer to const.
* src/symlist.h: Likewise.
* tests/named-refs.at (Misleading references): These are now caught
by the C compiler, not by Bison; that's good enough. Adjust test
to reflect this.
(Many kinds of errors, Unresolved references): Adjust expected
diagnostics to match new behavior. The same errors are caught,
though the diagnostics are not quite as fancy.
($ or @ followed by . or -): Likewise. Also, Make the grammar
unambiguous, so that diagnostics are not complicated by ambiguity
warnings.
Reported by Paul Hilfinger as a side effect of named references
support at
<http://lists.gnu.org/archive/html/bug-bison/2011-01/msg00000.html>.
Suggested by Paul Eggert.
* src/scan-code.l ({letter}, {id}): Adjust lexical definitions.
* src/scan-gram.l ({letter}, {id}): Likewise.
Reported by Paul Hilfinger as a side effect of named references
support at
<http://lists.gnu.org/archive/html/bug-bison/2011-01/msg00000.html>.
Suggested by Paul Eggert.
* src/scan-code.l ({letter}, {id}): Adjust lexical definitions.
* src/scan-gram.l ({letter}, {id}): Likewise.
These changes allow users to prefix an action with %? to indicate that it
is a semantic predicate---an expression that is evaluated immediately (not
deferred, even in GLR nondeterministic mode) and causes a syntax error if
false. In GLR parsers, this has the effect of killing one of a set of
split-off parses, just as would an ordinary syntax error.
Changelog:
* NEWS: Describe new semantic-predicate feature.
* data/c.m4 (b4_predicate_case): New definition.
* data/java.m4 (b4_predicate_case): New definition.
* data/glr.c (yyimmediate): Add definition.
(yydoAction): Remove comment, now obsolete.
Do YY_REDUCE_PRINT here.
(yyglrReduce): Alter comment to indicate that semantic values
need not be deferred.
Remove YY_REDUCE_PRINT from here; done in yydoAction.
(yyprocessOneStack): Pass immediate flag.
Delete stacks rejected by predicates in newly split-off parsers.
Change handling of yyerr so that only current stack gets deleted
when semantic predicate fails.
(yyfillin): Don't crash if a semantic value is unresolved (as may
happen in predicate rules).
Copy lr state as well in debugging mode.
Update comment on setting of yysval to include yyloc as well.
(yy_reduce_print): Add yynormal argument. Perform fillin properly.
Report unresolved RHS values.
(yyimmediate): New table.
* src/gram.h (struct rule): Add is_predicate field.
* src/output.c (user_actions_output): Use b4_predicate_case for
predicates.
(prepare_symbols): Output yyimmediate.
* src/scan-gram.l: Add %? token, SC_PREDICATE state.
* src/scan-code.l (code_props_rule_action_init): Add is_predicate
argument.
* src/scan-code.h (struct code_props): Add is_predicate field.
(code_props_rule_action_init): New interface.
* src/parse-gram.y (%?{...}): New token.
(rhs): Add %?{...} rule.
* src/parse-gram.c: Regenerate.
* src/parse-gram.h: Regenerate.
* src/reader.c (grammar_current_rule_action_append): Add
immediate argument.
(grammar_midrule_action): Use new interface for
code_props_rule_action_init.
(grammar_current_rule_action_append): Ditto.
(packgram): Transfer is_predicate value.
* src/reader.h (grammar_current_rule_action_append): New interface.
* doc/bison.texinfo: Document semantic predicates (%?).
* data/glr.c (yylhsNonterm, yyisDefaultedState,yyDefaultAction)
(yygetLRActions,yynewGLRStackItem,yyaddDeferredAction,yyinitStateSet)
(yyinitGLRStack,yyexpandGLRStack,yyupdateSplit,yymarkStackDeleted)
(yyundeleteLastStack,yyglrShift,yyglrShiftDefer,yydoAction,yyglrReduce)
(yyidenticalOptions,yymergeOptionSets,yyresolveStates,yyresolveAction)
(yyresolveLocations,yyresolveValue,yyreducePrint): Update parameter
names in comments and mention all parameters.
(struct yyGLRState): Fix description of yyposn field.
(yyresolveLocations): Correct comment so as not to imply action when
yyn1==0.
Provide a means to factor lex-param and parse-param common
declarations.
* src/parse-gram.y (param_type): New.
Define a %printer for it.
(add_param): Use it.
(%parse-param, %lex-param): Merge into...
(%parse): this new token.
Adjust the grammar to use it.
* src/scan-gram.l (RETURN_VALUE): New.
(RETURN_PERCENT_FLAG): Use it.
(RETURN_PERCENT_PARAM): New.
Use it to support %parse-param, %lex-param and %param.
Discussed starting at
<http://lists.gnu.org/archive/html/bison-patches/2009-08/msg00036.html>.
* src/scan-gram.l (SC_ESCAPED_STRING, SC_ESCAPED_CHARACTER):
For a \0 and similar escape sequences meaning the null
character, report an invalid escape sequence instead of an
invalid null character because the latter does not actually
appear in the user's input.
In all escape sequence complaints, don't escape the initial
backslash, and don't quote when the sequence appears at the end
of the complaint line unless there's whitespace that quotearg
won't escape.
Consistently say "invalid" not "unrecognized".
Consistently prefer "empty character literal" over "extra
characters in character literal" warning for invalid escape
sequences; that is, consistently discard those sequences.
* tests/input.at (Bad escapes in literals): New.
(cherry picked from commit c2724603c9)
Discussed starting at
<http://lists.gnu.org/archive/html/bison-patches/2009-08/msg00036.html>.
* src/scan-gram.l (SC_ESCAPED_STRING, SC_ESCAPED_CHARACTER):
For a \0 and similar escape sequences meaning the null
character, report an invalid escape sequence instead of an
invalid null character because the latter does not actually
appear in the user's input.
In all escape sequence complaints, don't escape the initial
backslash, and don't quote when the sequence appears at the end
of the complaint line unless there's whitespace that quotearg
won't escape.
Consistently say "invalid" not "unrecognized".
Consistently prefer "empty character literal" over "extra
characters in character literal" warning for invalid escape
sequences; that is, consistently discard those sequences.
* tests/input.at (Bad escapes in literals): New.
* src/reader.c (reader): Move %define front-end variable
defaults and checking into...
(prepare_percent_define_front_end_variables): ... this new
function.
* src/scan-gram.l (INITIAL): For consistency with string
literals, don't store open quote on character literal. It's
discarded before returning anyway.
(SC_ESCAPED_CHARACTER): Similarly, don't store close quote.
Make length test more readable, and make the character stored
for an empty literal more obvious while consistent with the
previous behavior.
* src/symtab.c, src/symtab.h: Rename USER_NUMBER_ALIAS to
USER_NUMBER_HAS_STRING_ALIAS throughout.
* src/symtab.c (symbol_make_alias): Remove comment from symtab.c
that is repeated in symtab.h. Improve argument names to make it
clear which side of the symbol-string alias pair is which.
(symbol_check_alias_consistency): Improve local variable names
for the same purpose.
* src/symtab.h (struct symbol): Make comments about aliases
clearer.
(symbol_make_alias): Improve comments and argument name.
* src/output.c (token_definitions_output): Update for rename to
USER_NUMBER_HAS_STRING_ALIAS and improve comments about aliases.
(cherry picked from commit dfaa48602d)
Conflicts:
src/symtab.c
src/symtab.h
* src/reader.c (reader): Move %define front-end variable
defaults and checking into...
(prepare_percent_define_front_end_variables): ... this new
function.
* src/scan-gram.l (INITIAL): For consistency with string
literals, don't store open quote on character literal. It's
discarded before returning anyway.
(SC_ESCAPED_CHARACTER): Similarly, don't store close quote.
Make length test more readable, and make the character stored
for an empty literal more obvious while consistent with the
previous behavior.
* src/symtab.c, src/symtab.h: Rename USER_NUMBER_ALIAS to
USER_NUMBER_HAS_STRING_ALIAS throughout.
* src/symtab.c (symbol_make_alias): Remove comment from symtab.c
that is repeated in symtab.h. Improve argument names to make it
clear which side of the symbol-string alias pair is which.
(symbol_check_alias_consistency): Improve local variable names
for the same purpose.
* src/symtab.h (struct symbol): Make comments about aliases
clearer.
(symbol_make_alias): Improve comments and argument name.
* src/output.c (token_definitions_output): Update for rename to
USER_NUMBER_HAS_STRING_ALIAS and improve comments about aliases.
Reported by Alex Rozenman. This warning shows up with gcc-4.3.0
and later.
* src/scan-code.l: Add "%option noinput", which I cannot find in
the Flex manual, but which Flex has supported since at least as
far back as 2.5.4. However, if any of our developers still use
Flex 2.5.4, they'll need to stop configuring with
--enable-gcc-warnings because "%option noinput" didn't work
correctly until Flex 2.5.6.
* src/scan-gram.l: Likewise.
* src/scan-skel.l: Likewise.
(cherry picked from commit 42f8609bbd)
Reported by Alex Rozenman. This warning shows up with gcc-4.3.0
and later.
* src/scan-code.l: Add "%option noinput", which I cannot find in
the Flex manual, but which Flex has supported since at least as
far back as 2.5.4. However, if any of our developers still use
Flex 2.5.4, they'll need to stop configuring with
--enable-gcc-warnings because "%option noinput" didn't work
correctly until Flex 2.5.6.
* src/scan-gram.l: Likewise.
* src/scan-skel.l: Likewise.
(cherry picked from commit 42f8609bbd)
* NEWS (2.5): Document.
* src/scan-gram.l (INITIAL): Remove comment that we don't check
the length.
(SC_ESCAPED_CHARACTER): Warn if length is wrong.
* tests/input.at (Bad character literals): New test group.
(cherry picked from commit ac9b0e954b)
* NEWS (2.5): Document.
* src/scan-gram.l (INITIAL): Remove comment that we don't check
the length.
(SC_ESCAPED_CHARACTER): Warn if length is wrong.
* tests/input.at (Bad character literals): New test group.
* src/named-ref.h: Add comments.
* src/parse-gram.y: Readability and style changes.
* src/reader.c: Factoring: assign_named_ref function.
* src/scan-code.l: Factoring and style changes. Rename
parse_named_ref to parse_ref. Use "c-ctype.h" from gnulib.
Use "unsigned" type for variant index. Improve readablity.
* src/scan-gram.l: Change error messages and add comments.
* src/symlist.h: symbol_list_null: New function decl.
* src/symlist.c: symbol_list_null: Implement here.
* tests/named-refs.at: Adjust for new error messages.
* src/named-ref.h: Add comments.
* src/parse-gram.y: Readability and style changes.
* src/reader.c: Factoring: assign_named_ref function.
* src/scan-code.l: Factoring and style changes. Rename
parse_named_ref to parse_ref. Use "c-ctype.h" from gnulib.
Use "unsigned" type for variant index. Improve readablity.
* src/scan-gram.l: Change error messages and add comments.
* src/symlist.h: symbol_list_null: New function decl.
* src/symlist.c: symbol_list_null: Implement here.
* tests/named-refs.at: Adjust for new error messages.
Implement, document, and test the replacement of %error-verbose
by %define parse.error "verbose".
* data/bison.m4 (b4_error_verbose_if): Reimplement to track the
values of the parse.error variable.
Make "simple" its default value.
Check the valid values.
* src/parse-gram.y: Use %define parse.error.
(PERCENT_ERROR_VERBOSE): New token.
Support it.
* src/scan-gram.l: Support %error-verbose.
* doc/bison.texinfo (Decl Summary): Replace the documentation of
%define error-verbose by that of %define parse.error.
* NEWS: Document it.
* tests/actions.at, tests/calc.at: Use parse.error instead of
%error-verbose.
Discussed in:
http://lists.gnu.org/archive/html/bison-patches/2009-01/msg00000.htmlhttp://lists.gnu.org/archive/html/bison-patches/2009-02/msg00002.htmlhttp://lists.gnu.org/archive/html/bison-patches/2009-03/msg00009.html
* src/parse-gram.y: Add new syntax (named_ref.opt).
* src/reader.c: Store named refs in symbol lists.
* src/reader.h: New argument for symbol_append and
action_append functions.
* src/scan-code.h: Add new field (named_ref) into
code_props data structure. Keeps named ref of midrule
actions.
* src/scan-code.l: Support for named refs in semantic
action code. New function 'parse_named_ref'.
* src/scan-gram.l: Support bracketed id.
* src/symlist.c: Store named refs in symbol lists.
* src/symlist.h: New field in symbol list: named_ref.
* src/named-ref.h: New file, a struct for named_ref.
* src/named-ref.c: New file, named_ref_new function.
* src/Makefile.am: Add two new files.
* tests/testsuite.at: Include new test group:
* tests/named-refs.at: this new file.
Discussed in:
http://lists.gnu.org/archive/html/bison-patches/2009-01/msg00000.htmlhttp://lists.gnu.org/archive/html/bison-patches/2009-02/msg00002.htmlhttp://lists.gnu.org/archive/html/bison-patches/2009-03/msg00009.html
* src/parse-gram.y: Add new syntax (named_ref.opt).
* src/reader.c: Store named refs in symbol lists.
* src/reader.h: New argument for symbol_append and
action_append functions.
* src/scan-code.h: Add new field (named_ref) into
code_props data structure. Keeps named ref of midrule
actions.
* src/scan-code.l: Support for named refs in semantic
action code. New function 'parse_named_ref'.
* src/scan-gram.l: Support bracketed id.
* src/symlist.c: Store named refs in symbol lists.
* src/symlist.h: New field in symbol list: named_ref.
* src/named-ref.h: New file, a struct for named_ref.
* src/named-ref.cp: New file, named_ref_new function.
* src/local.mk: Add two new files.
* tests/testsuite.at: Include new test group:
* tests/named-refs.at: this new file.
* src/scan-gram.l ({id}): Also accept dashes after the initial
letter.
({directive}): Use {id}.
* src/parse-gram.y: Comment and formatting changes.
* doc/bison.texinfo (Symbols): Adjust the lexical definitions of
symbols.
* src/complain.h, src/complain.c (yacc_at): New.
* src/symtab.c (symbol_new): Use yacc_at to report inappropriate
symbol names.
* src/output.c (token_definitions_output): Do not #define token
names with dashes.
(cherry picked from commit 4f646c3794)
Conflicts:
data/bison.m4
src/parse-gram.y
* data/bison.m4 (b4_percent_define_if_define_): Also map dashes to
underscores.
* src/scan-gram.l ({id}): Also accept dashes after the initial
letter.
({directive}): Use {id}.
* src/parse-gram.y: Comment and formatting changes.
* doc/bison.texinfo (Symbols): Adjust the lexical definitions of
symbols.
* src/complain.h, src/complain.c (yacc_at): New.
* src/symtab.c (symbol_new): Use yacc_at to report inappropriate
symbol names.
* src/output.c (token_definitions_output): Do not #define token
names with dashes.
* src/getargs.h, src/getargs.c (locations_flag): Remove.
* src/getargs.c, src/scan-code.l: Use muscle_percent_define_ensure
to set "locations" to true.
* src/output.c (prepare): Don't output "locations".
* src/scan-gram.l (%locations): Handle it as a %<flag>.
* src/parse-gram.y: It's no longer a token.
Don't handle it.
* data/bison.m4 (b4_locations_if): Define it with
b4_percent_define_if_define.
* data/c.m4, data/glr.cc: Adjust.
Suggested by Joel E. Denny.
* src/muscle_tab.h, src/muscle_tab.c (muscle_percent_define_ensure):
New, extracted from...
* src/parse-gram.y (prologue_declaration: pure-parser): here.
Remove it.
(prologue_declaration: "%<flag>"): Use
muscle_percent_define_ensure.
(%error-verbose, %pure-parser): No longer tokens.
* src/scan-gram.l (pure-parser): Return as a %<flag>.
* doc/bison.texinfo (-g, -x): Add space before argument.
(Option Cross Key): Implement FIXME: listing directives also.
* build-aux/cross-options.pl: Read from <STDIN> rather than <>.
(Short Option): Special case -d. Put arguments inside @option.
(Bison Directive): Add column, automatically extracted from
src/scan-gram.l (actual name passed as the first argument)
with special case for %define.
* doc/Makefile.am (doc/cross-options.texi): Pass src/scan-gram.l
to build-aux/cross-options.pl.
* src/getargs.c (usage): Document limitations of cross-options.pl.
* src/scan-gram.l: Likewise.
* src/parse-gram.y (PERCENT_DEBUG, PERCENT_ERROR_VERBOSE): Token
definitions and associated rules, replaced by....
(PERCENT_FLAG): this new token type, and rule.
* src/scan-gram.l (RETURN_PERCENT_FLAG): New.
Use it for %debug and %error-verbose.
* doc/bison.texinfo (-g, -x): Add space before argument.
(Option Cross Key): Implement FIXME: listing directives also.
* build-aux/cross-options.pl: Read from <STDIN> rather than <>.
(Short Option): Special case -d. Put arguments inside @option.
(Bison Directive): Add column, automatically extracted from
src/scan-gram.l (actual name passed as the first argument)
with special case for %define.
* doc/local.mk (doc/cross-options.texi): Pass src/scan-gram.l
to build-aux/cross-options.pl.
* src/getargs.c (usage): Document limitations of cross-options.pl.
* src/scan-gram.l: Likewise.
There are two issues to handle: first scanning nested angle bracket pairs
to support types such as std::pair< std::string, std::list<std::string> > >.
Another issue is to address idiosyncracies of C++: do not glue two closing
angle brackets together (otherwise it's operator>>), and avoid sticking
blindly a TYPE to the opening <, as it can result in '<:' which is a
digraph for '['.
* src/scan-gram.l (brace_level): Rename as...
(nesting): this.
(SC_TAG): New.
Implement support for complex tags.
(tag): Accept \n, but not <.
* data/lalr1.cc (b4_symbol_value, b4_symbol_value_template)
(b4_symbol_variant): Leave space around types as parameters.
* examples/variant.yy: Use nested template types and leading ::.
* src/parse-gram.y (TYPE, TYPE_TAG_ANY, TYPE_TAG_NONE, type.opt):
Rename as...
(TAG, TAG_ANY, TAG_NONE, tag.opt): these.
* tests/c++.at: Test parametric types.
* src/Makefile.am: Rename as...
* src/local.mk: this.
Prefix all the paths with src/.
(AUTOMAKE_OPTIONS): Build object files in the sub dirs.
(AM_CPPFLAGS): Find find in builddir/src.
(YACC): Move the flags into...
(AM_YFLAGS): here.
* maint.mk (sc_tight_scope): Disable.
It used to bounce to the version in src/Makefile.am which is now
part of this very Makefile.
* Makefile.am, configure.ac: Adjust.
* src/scan-code-c.c, src/scan-code.l: We can no longer rely on
include "..." to find files "here": we are no longer in src/, so
qualify the includes with src/.
* doc/Makefile.am (PREPATH): No longer include the top_builddir
prefix.
(.x.1): Adjust to be able to create src/foo from the top level
Makefile, instead of going bounce to src/Makefile the creation of
foo.
