mirror of
https://github.com/heqin-zhu/algorithm.git
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99 lines
2.0 KiB
Markdown
99 lines
2.0 KiB
Markdown
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# C-parser
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>A token\_scanner and declaration parser for simplified c using LL(1)
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# Rules
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* size of int or pointer is 1byte
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# Grammar
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```scala
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translation_unit
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: declaration
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| translation_unit declaration
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;
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declaration
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: declaration_specifiers init_declarator_list ';'
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;
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declaration_specifiers
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: type_specifier
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;
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init_declarator_list
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: init_declarator
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| init_declarator_list ',' init_declarator
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;
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init_declarator
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: declarator
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;
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type_specifier
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: VOID
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| INT
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;
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declarator
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: pointer direct_declarator
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| direct_declarator
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;
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direct_declarator
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: IDENTIFIER
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| '(' declarator ')'
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| direct_declarator '[' CONSTANT_INT ']'
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| direct_declarator '(' parameter_type_list ')'
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| direct_declarator '(' ')'
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;
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pointer
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: '*'
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| '*' pointer
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;
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parameter_type_list
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: parameter_list
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;
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parameter_list
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: parameter_declaration
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| parameter_list ',' parameter_declaration
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;
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parameter_declaration
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: declaration_specifiers declarator
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;
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```
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# Examples
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```c
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>> int *p,q,j[2];
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p::pointer(int)
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q::int
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j::array(2,int)
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>> int *p[2][3];
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p::array(2,array(3,pointer(int)))
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>> int (*p[4])[2];
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p::array(4,pointer(array(2,int)))
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>> int (*f(int i,void *j))[2];
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f::function( i::int X j::pointer(void) => pointer(array(2,int)))
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>> int f(void i, void j, int p[2]);
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f::function( i::void X j::void X p::array(2,int) => int)
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>> int *f(int i)[2];
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[Error]: Array of Functions is not allowed
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>> int f[2](int k);
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[Error]: Array of Function can not be returned from functions
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>> void (*(*paa)[10])(int a);
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paa::pointer(array(10,pointer(function( a::int => void))))
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>> int (*(*(*pg())(int x))[20])(int *y);
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pg::function( void => pointer(function( x::int => pointer(array(20,pointer(function( y::pointer(int) => int)))))))
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>> int (*p(int * s,int (*t)(int *m, int n, int (*l())[20]),int k[10]))[10][20];
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p::function( s::pointer(int) X t::pointer(function( m::pointer(int) X n::int X l::function( void => pointer(array(20,int))) => int)) X k::array(10,int) => pointer(array(10,array(20,int))))
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```
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