102 lines
1.8 KiB
Markdown
102 lines
1.8 KiB
Markdown
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Micro Parser Combinators
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========================
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_mpc_ is a lightweight Parser Combinator library for C.
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The current main alternative is a branch of (https://github.com/wbhart/Cesium3)[Cesium3].
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Features & Advantages
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---------------------
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* Error Message Support
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* Regular Expression Support
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* Parser Grammar Support
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* Works for Generic Types
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* AST Extension
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* Single source & header files
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* Written in clean ANSI C
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* Doesn't rely on Boehm-Demers-Weiser Garbage Collection
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* Doesn't use `setjmp` and `longjmp` for errors
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* Doesn't pollute namespace
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Example
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-------
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```c
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mpc_val_t* combine_maths(int n, mpc_val_t** xs) {
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int** vs = (int**)xs;
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if (*vs[1] == '*') { *vs[0] *= *vs[2]; }
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if (*vs[1] == '/') { *vs[0] /= *vs[2]; }
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if (*vs[1] == '+') { *vs[0] += *vs[2]; }
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if (*vs[1] == '-') { *vs[0] -= *vs[2]; }
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free(vs[1]);
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free(vs[2]);
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return vs[0];
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}
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int main(int argc, char** argv) {
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mpc_parser_t* Expr = mpc_new();
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mpc_parser_t* Factor = mpc_new();
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mpc_parser_t* Term = mpc_new();
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mpc_parser_t* Maths = mpc_new();
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mpc_define(Expr,
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mpc_pc("cmaths ( fact ['*' | '/'] fact ) | fact",
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combine_maths, Factor, free, Factor, free, Factor),
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);
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mpc_define(Factor,
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mpc_pc("cmaths ( term ['+' | '-'] term ) | term",
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combine_maths, Term, free, Term, free, Term),
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);
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mpc_define(Term,
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mpc_pc("num | snd ('(' expr ')')",
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mpc_int(), mpcf_asnd_free, Expr, free)
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);
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mpc_define(Maths, mpc_ends(Expr, free));
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mpc_delete(Expr);
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mpc_delete(Factor);
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mpc_delete(Term);
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mpc_delete(Maths);
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}
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```
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Parsers
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-------
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Combinators
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-----------
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Regular Expressions
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-------------------
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Combinator Grammars
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-------------------
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Abstract Syntax Tree
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--------------------
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Reference
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---------
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