Commit Graph

10 Commits

Author SHA1 Message Date
Akim Demaille
8637438cee yacc.c: isolate yyexpected_tokens
Provide users with a means to query for the currently allowed tokens.
Could be used for autocompletion for instance.

* data/skeletons/yacc.c (yyexpected_tokens): New, extracted from
yysyntax_error_arguments.
* examples/c/calc/calc.y (PRINT_EXPECTED_TOKENS): New.
Use it.
2020-01-17 06:49:59 +01:00
Akim Demaille
cda1934606 yacc.c: add custom error message generation
When parse.error is custom, let users define a yyreport_syntax_error
function, and use it.

* data/skeletons/bison.m4 (b4_error_verbose_if): Accept 'custom'.
* data/skeletons/yacc.c: Implement it.
* examples/c/calc/calc.y: Experiment with it.
2020-01-17 06:49:59 +01:00
Akim Demaille
8036635251 package: bump copyrights to 2020
Run 'make update-copyright'.
2020-01-05 10:26:35 +01:00
Akim Demaille
02a1600994 package: add missing CLEANFILES
* examples: here.
2019-04-28 11:39:10 +02:00
Akim Demaille
0cc04eaa2a package: don't ship the sources generated from the parser
Because some of our examples use

    %C%_reccalc_SOURCES = %D%/parse.y

Automake ships parse.y and parse.c, and possibly parse.h when it
"understands" that there is one.  This is not what we want: ship only
parser.y.  Yet we still want to use Automake to compile the sources
from parser.y.  The easiest seems to use

    nodist_%C%_reccalc_SOURCES = %D%/parse.y

together with

    dist_reccalc_DATA = %D%/parse.y %D%/scan.l %D%/Makefile %D%/README.md

which guarantees that parse.y is indeed shipped.

* examples/c/calc/local.mk, examples/c/lexcalc/local.mk,
* examples/c/reccalc/local.mk: Always use nodist_*SOURCES for parsers,
let the dist_*_DATA rules do their job.
2019-04-28 11:39:10 +02:00
Akim Demaille
57290d63fd package: various fixes for syntax-check
* cfg.mk: Disable checks where needed (e.g., we do want to check the
behavior with tabs).
(sc_at_parser_check): Remove.  Unfortunately since
a11c144609 we no longer use the './'
prefix to run programs in the current directory.  That was so that we
could run Java programs like the other, although they are no run with
the `./` prefix (see 967a59d2c0).
As a consequence this sc check no longer makes sense.
However, since now AT_PARSER_CHECK passes the `./` prefix itself, this
sc-check was superfluous.
* examples/c/reccalc/scan.l: Use memcpy, not strncpy.
* src/ielr.c, src/reader.c: Obfuscate "lr(0)" so that the sc-check for
"space before paren" does not fire.
* tests/diagnostics.at: Avoid space-tab, use tab-tab.
2019-04-28 08:24:31 +02:00
Akim Demaille
4e19ab9fcd yacc.c: provide a means to include the header in the implementation
Currently when --defines is used, we generate a header, and paste an
exact copy of it into the generated parser implementation file.  Let's
provide a means to #include it instead.

We don't do it by default because of the Autotools' ylwrap.  This
program wraps invocations of yacc (that uses a fixed output name:
y.tab.c, y.tab.h, y.output) to support a more modern naming
scheme (dir/foo.y -> dir/foo.tab.c, dir/foo.tab.h, etc.).  It does
that by renaming the generated files, and then by running sed to
propagate these renamings inside the files themselves.

Unfortunately Automake's Makefiles uses Bison as if it were Yacc (with
--yacc or with -o y.tab.c) and invoke bison via ylwrap.  As a
consequence, as far as Bison is concerned, the output files are
y.tab.c and y.tab.h, so it emits '#include "y.tab.h"'.  So far, so
good.  But now ylwrap processes this '#include "y.tab.h"' into
'#include "dir/foo.tab.h"', which is not guaranteed to always work.

So, let's do the Right Thing when the output file is not y.tab.c, in
which case the user should %define api.header.include.  Binding this
behavior to --yacc is tempting, but we recently told people to stop
using --yacc (as it also enables the Yacc warnings), but rather to use
-o y.tab.c.

Yacc.c is the only skeleton concerned: all the others do include their
header.

* data/skeletons/yacc.c (b4_header_include_if): New.
(api.header.include): Provide a default value when the output is not
y.tab.c.
* src/parse-gram.y (api.header.include): Define.
2019-03-17 16:36:05 +01:00
Akim Demaille
5230e610fc style: minor changes
* examples/c/calc/calc.y, src/lalr.c: Reduce scope.
* src/gram.c: Prefer < to >.
2019-02-24 19:08:01 +01:00
Akim Demaille
8cbf3ce22c examples: depend on Bison's sources
* examples/c/calc/local.mk, examples/c/lexcalc/local.mk,
* examples/c/mfcalc/local.mk, examples/c/rpcalc/local.mk:
Regenerate the files if dependencies have changed.
2019-02-12 06:19:10 +01:00
Akim Demaille
40fc688765 examples: add a simple infix calculator in C
Currently we have no simple example: rpcalc in reverse Polish, mfcalc
has functions, and lexcalc is using lex.

* examples/c/calc/Makefile, examples/c/calc/calc.y,
* examples/c/calc/calc.test, examples/c/calc/local.mk: New.
2019-02-10 17:44:23 +01:00