Suggested by Joe Nelson <joe@begriffs.com>.
https://lists.gnu.org/r/help-bison/2020-12/msg00020.html
* data/skeletons/glr.c, data/skeletons/yacc.c (YYNOMEM): New.
Use it.
(yyexhaustedlab): Rename as...
(yynomemlab): this.
* tests/calc.at: Check it.
* doc/bison.texi: Document it.
Fix incorrect statements about non-existing constants for YYERROR etc.
Without the history, D should not support this option. Before the
removal, 'detailed' and 'verbose' options generated the same code.
* data/skeletons/lalr1.d: Here.
* doc/bison.texi: Adapt tests to use 'detailed' instead of 'verbose'.
* tests/calc.at: Document it.
The D parser implements this feature similarly to the C parser,
by using Gettext. Functions gettext() and dgettext() are
imported using extern(C). The internationalisation uses yysymbol_name
to report the name of the SymbolKinds.
* data/skeletons/d.m4 (SymbolKind.toString.yytranslatable,
SymbolKind.toString.yysymbol_name: New), data/skeletons/lalr1.d: Here.
* doc/bison.texi: Document it.
* tests/calc.at: Test it.
We always refer to the triplet "kind, value, location". All of them
are nouns, and we support api.value.type and api.location.type. On
this regard, "semantic_type" was a poor choice. Make it "value_type".
The test suite was not updated to use value_type, on purpose, to
enforce backward compatibility.
* data/skeletons/c++.m4, data/skeletons/glr.cc, data/skeletons/glr2.cc,
* data/skeletons/variant.hh, doc/bison.texi: Define value_type rather
than semantic_type.
Add a backward compatibility typedef.
* examples/c++/glr/c++-types.yy: Migrate.
The complete symbol approach in yylex removes the need for the methods
semanticVal, startPos and endPos, which were used when the values were
reported separately.
* data/skeletons/lalr1.d: Here.
* doc/bison.texi: Remove sections about the three methods.
* examples/d/calc/calc.y, examples/d/simple/calc.y: Remove the unused methods.
* tests/calc.at, tests/d.at, tests/scanner.at: Test it.
* data/skeletons/d.m4 (b4_public_types_declare): Here.
* data/skeletons/lalr1.d: Adjust.
* doc/bison.texi: Document it.
* examples/d/calc/calc.y: Use it.
* tests/calc.at: Test it.
This avoids heap allocation and gives minimal costs for the
creation and destruction of the YYParser.Symbol struct if
the location tracking is active.
Suggested by H. S. Teoh.
* data/skeletons/lalr1.d: Here.
* doc/bison.texi: Document it.
* examples/d/calc/calc.y: Adjust.
* tests/calc.at: Test it.
The complete symbol approach was deemed to be the right approach for Dlang.
Now, the user can return from yylex() an instance of YYParser.Symbol structure,
which binds together the TokenKind, the semantic value and the location. Before,
the last two were reported separately to the parser.
Only the user API is changed, Bisons's internal structure is kept the same.
* data/skeletons/d.m4 (struct YYParser.Symbol): New.
* data/skeletons/lalr1.d: Change the return value.
* doc/bison.texi: Document it.
* examples/d/calc/calc.y, examples/d/simple/calc.y: Demonstrate it.
* tests/calc.at, tests/scanner.at: Test it.
When using lookahead correction, the method YYParser.Context.getExpectedTokens
is not annotated with const, because the method calls yylacCheck, which is not
const. Also, because of yylacStack and yylacEstablished, yylacCheck needs to
be called from the context of the parser class, which is sent as parameter to
the Context's constructor.
* data/skeletons/lalr1.d (yylacCheck, yylacEstablish, yylacDiscard,
yylacStack, yylacEstablished): New.
(Context): Use it.
* doc/bison.texi: Document it.
* tests/calc.at: Check it.
Changed from syntax_error to reportSyntaxError to be similar to the Java parser.
* data/skeletons/lalr1.d: Change the function name.
* doc/bison.texi: Document it.
* tests/local.at: Adjust.
* maint:
c++: shorten the assertions that check whether tokens are correct
c++: don't glue functions together
lalr1.cc: YY_ASSERT should use api.prefix
c++: don't use YY_ASSERT at all if parse.assert is disabled
c++: style: follow the Bison m4 quoting pattern
yacc.c: provide the Bison version as an integral macro
regen
style: make conversion of version string to int public
%require: accept version numbers with three parts ("3.7.4")
yacc.c: fix #definition of YYEMPTY
gnulib: update
doc: fix incorrect section title
doc: minor grammar fixes in counterexamples section
Parser.Context class returns a const YYLocation, so Lexer's method
yyerror() needs to receive the location as a const parameter.
Internal error reporting flow is changed to be similar to that of
the other skeletons. Before, case YYERRLAB was calling yyerror()
with the result of yysyntax_error() as the string parameter. As the
custom error message lets the user decide if they want to use
yyerror() or not, this flow needed to be changed. Now, case YYERRLAB
calls yyreportSyntaxError(), that builds the error message using
yysyntaxErrorArguments(). Then yyreportSyntaxError() passes the
error message to the user defined syntax_error() in case of a custom
message, or to yyerror() otherwise.
In the tests in tests/calc.at, the order of the tokens needs to be
changed in order of precedence, so that the D program outputs the
expected tokens in the same order as the other parsers.
* data/skeletons/lalr1.d: Add the custom error message feature.
* doc/bison.texi: Document it.
* examples/d/calc/calc.y: Adjust.
* tests/calc.at, tests/local.at: Test it.
This will provide the user an interface for creating custom error messages.
* data/skeletons/lalr1.d: Add the Context class.
* doc/bison.texi: Document it.
This is consistent with --defines being deprecated in favor of
--header. The directive %defines is also too similar to %define.
And %header matches nicely with api.header.name.
* src/scan-gram.l (%defines): Deprecate to %header.
(%header): Scan it.
* src/parse-gram.y (PERCENT_DEFINES): Replace with...
(PERCENT_HEADER): this.
* data/skeletons/lalr1.java
* doc/bison.texi
* tests/actions.at, tests/c++.at, tests/calc.at, tests/conflicts.at,
* tests/input.at, tests/java.at, tests/local.at, tests/output.at,
* tests/synclines.at, tests/types.at:
Convert most tests to check %header instead of %defines.
The name "defines" is incorrect, the generated file contains far more
than just #defines.
* src/getargs.h, src/getargs.c (-H, --header): New option.
With optional argument, just like --defines, --xml, etc.
(defines_flag): Rename as...
(header_flag): this.
Adjust dependencies.
* data/skeletons/bison.m4, data/skeletons/c.m4, data/skeletons/glr.c,
* data/skeletons/glr.cc, data/skeletons/glr2.cc, data/skeletons/lalr1.cc,
* data/skeletons/yacc.c:
Adjust.
* examples, doc/bison.texi: Adjust.
* tests/headers.at, tests/local.at, tests/output.at: Convert most
tests from using --defines to using --header.
On a case such as
%%
exp
: empty "a"
| "a" empty
empty
: %empty
we used to display
warning: shift/reduce conflict on token "a" [-Wcounterexamples]
Example: • "a"
Shift derivation
exp
↳ 2: • "a" empty
↳ 2: ε
Example: • "a"
Reduce derivation
exp
↳ 1: empty "a"
↳ 3: •
where the shift derivation shows an item "2: empty → ε", with an
explicit "ε", but the reduce derivation shows "3: empty → •", without
"ε".
For consistency, let's always show ε/%empty in rules with an empty
rhs:
Reduce derivation
exp
↳ 1: empty "a"
↳ 3: ε •
* src/derivation.c (derivation_width, derivation_print_tree_impl):
Always show ε/%empty in counterexamples.
* tests/diagnostics.at: Check that case.
* tests/conflicts.at, tests/counterexample.at: Adjust.
The original Texinfo macros introducing colors were made for
diagnostics, which are printed in bold. So by copy-paste accident the
styles we introduced for counterexamples were also in bold. They
should not.
* doc/bison.texi: Separate the styling of diagnostics from the styling
for counterexamples.
Don't use bold in the latter case.
Unfortunately I found no way to use the ↳ glyph in Texinfo, so I used
@arrow{} instead, which has a different width, so we have to have all
the examples doubled, once for TeX, another for the rest of the world.
* doc/bison.texi: Use the current display in the examples.
* doc/calc.y, doc/ids.y, doc/if-then-else.y, doc/sequence.y: New.
Unfortunately Texinfo somewhat mangles anchors such as `-Werror` into
`g_t_002dWerror`, so let's not include the dash.
* doc/bison.texi (Diagnostics): here.
When reporting counterexamples for s/r conflicts, put the shift first.
This is more natural, and displays the default resolution first, which
is also what happens for r/r conflicts where the smallest rule number
is displayed first, and "wins".
* src/counterexample.c (counterexample): Add a shift_reduce member.
(new_counterexample): Adjust.
Swap the derivations when this is a s/r conflict.
(print_counterexample): For s/r conflicts, prefer "Shift derivation"
and "Reduce derivation" rather than "First/Second derivation".
* tests/conflicts.at, tests/counterexample.at, tests/report.at: Adjust.
* NEWS, doc/bison.texi: Ditto.
It does not make a lot of sense to use ::= in our counterexamples,
that's not something that belongs to the Bison "vocabulary". Using
the colon makes sense, but it's too discreet. Let's use the arrow,
which we already use in some reports (HTML and Dot).
* src/gram.h (print_dot_fallback): Generalize into...
(print_fallback): this.
(print_arrow): New.
* src/derivation.c: Use it.
* NEWS, tests/conflicts.at, tests/counterexample.at,
* tests/diagnostics.at, tests/report.at: Adjust.
* doc/bison.texi: Ditto.
Unfortunately the literal `→` is output as `↦`. So we need to use
@arrow.
