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44ac18d136
In push parsers, when asking for the list of expected tokens at some point, it makes no sense to build a yyparse_context_t: the yypstate alone suffices (the only difference being the lookahead). Instead of forcing the user to build a useless shell around yypstate, let's offer yypstate_expected_tokens. See https://lists.gnu.org/r/bison-patches/2020-03/msg00025.html. * data/skeletons/yacc.c (yypstate): Declare earlier, so that we can use it for... (yypstate_expected_tokens): this new function, when in push parsers. Adjust dependencies. * examples/c/bistromathic/parse.y: Simplify: use yypstate_expected_tokens. Style fixes. Reduce scopes (reported by Joel E. Denny).
bistromathic - all the bells and whistles
This example demonstrates best practices when using Bison.
- Its hand-written scanner tracks locations.
- Its interface is pure.
- Its interface is "incremental", well suited for interaction: it uses the push-parser API to feed the parser with the incoming tokens.
- It features an interactive command line with completion based on the
parser state, based on
yyexpected_tokens. - It uses a custom syntax error with location, lookahead correction and token internationalization.
- It supports debug traces with semantic values.
- It uses named references instead of the traditional $1, $2, etc.