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C 语言文法 ( C Language Grammar )

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%token IDENTIFIER CONSTANT STRING_LITERAL SIZEOF
%token TYPE_NAME

%token TYPEDEF EXTERN STATIC AUTO REGISTER
%token CHAR SHORT INT LONG SIGNED UNSIGNED FLOAT DOUBLE CONST VOLATILE VOID
%token STRUCT UNION ENUM

%token CASE DEFAULT IF ELSE SWITCH WHILE DO FOR GOTO CONTINUE BREAK RETURN

%start translation_unit
%%
translation_unit
	: external_declaration
	| translation_unit external_declaration
	;

external_declaration
	: function_definition
	| declaration
	;

function_definition
	: declaration_specifiers declarator declaration_list compound_statement
	| declaration_specifiers declarator compound_statement
	| declarator declaration_list compound_statement
	| declarator compound_statement
	;

declaration_list
	: declaration
	| declaration_list declaration
	;

declaration
	: declaration_specifiers ';'
	| declaration_specifiers init_declarator_list ';'
	;
	
declaration_specifiers
	: storage_class_specifier
	| storage_class_specifier declaration_specifiers
	| type_specifier
	| type_specifier declaration_specifiers
	| type_qualifier
	| type_qualifier declaration_specifiers
	;
	
specifier_qualifier_list
	: type_specifier specifier_qualifier_list
	| type_specifier
	| type_qualifier specifier_qualifier_list
	| type_qualifier
	        
type_qualifier_list
	: type_qualifier
	| type_qualifier_list type_qualifier
	;

type_qualifier
	: CONST
	| VOLATILE
	;
 
storage_class_specifier
	: TYPEDEF
	| EXTERN
	| STATIC
	| AUTO
	| REGISTER
	;

type_specifier
	: VOID
	| CHAR
	| SHORT
	| INT
	| LONG
	| FLOAT
	| DOUBLE
	| SIGNED
	| UNSIGNED
	| struct_or_union_specifier
	| enum_specifier
	| TYPE_NAME
	;

struct_or_union_specifier
	: struct_or_union IDENTIFIER '{' struct_declaration_list '}'
	| struct_or_union '{' struct_declaration_list '}'
	| struct_or_union IDENTIFIER
	;

struct_or_union
	: STRUCT
	| UNION
	;

struct_declaration_list
	: struct_declaration
	| struct_declaration_list struct_declaration
	;

struct_declaration
	: specifier_qualifier_list struct_declarator_list ';'
	;

struct_declarator_list
	: struct_declarator
	| struct_declarator_list ',' struct_declarator
	;

struct_declarator
	: declarator
	| ':' constant_expression
	| declarator ':' constant_expression
	;

enum_specifier
	: ENUM '{' enumerator_list '}'
	| ENUM IDENTIFIER '{' enumerator_list '}'
	| ENUM IDENTIFIER
	;

enumerator_list
	: enumerator
	| enumerator_list ',' enumerator
	;

enumerator
	: IDENTIFIER
	| IDENTIFIER '=' constant_expression
	;       
	
init_declarator_list
	: init_declarator
	| init_declarator_list ',' init_declarator
	;       

init_declarator
	: declarator
	| declarator '=' initializer
	;
	
initializer_list
	: initializer
	| initializer_list ',' initializer
	;        

initializer
	: assignment_expression
	| '{' initializer_list '}'
	| '{' initializer_list ',' '}'
	;

parameter_type_list
	: parameter_list
	| parameter_list ',' '...'
	;

parameter_list
	: parameter_declaration
	| parameter_list ',' parameter_declaration

parameter_declaration
	: declaration_specifiers declarator
	| declaration_specifiers abstract_declarator
	| declaration_specifiers
	;

identifier_list
	: IDENTIFIER
	| identifier_list ',' IDENTIFIER
	;

type_name
	: specifier_qualifier_list
	| specifier_qualifier_list abstract_declarator
	;

abstract_declarator
	: pointer
	| direct_abstract_declarator
	| pointer direct_abstract_declarator
	;

direct_abstract_declarator
	: '(' abstract_declarator ')'
	| '[' ']'
	| '[' constant_expression ']'
	| direct_abstract_declarator '[' ']'
	| direct_abstract_declarator '[' constant_expression ']'
	| '(' ')'
	| '(' parameter_type_list ')'
	| direct_abstract_declarator '(' ')'
	| direct_abstract_declarator '(' parameter_type_list ')'
	;

declarator
	: pointer direct_declarator
	| direct_declarator
	;

direct_declarator
	: IDENTIFIER
	| '(' declarator ')'
	| direct_declarator '[' constant_expression ']'
	| direct_declarator '[' ']'
	| direct_declarator '(' parameter_type_list ')'
	| direct_declarator '(' identifier_list ')'
	| direct_declarator '(' ')'
	;

pointer
	: '*'
	| '*' type_qualifier_list
	| '*' pointer
	| '*' type_qualifier_list pointer
	;        
	
statement
	: labeled_statement
	| compound_statement
	| expression_statement
	| selection_statement
	| iteration_statement
	| jump_statement
	;
	       
labeled_statement
	: IDENTIFIER ':' statement
	| CASE constant_expression ':' statement
	| DEFAULT ':' statement
	;

compound_statement
	: '{' '}'
	| '{' statement_list '}'
	| '{' declaration_list '}'
	| '{' declaration_list statement_list '}'
	;        
	     
statement_list
	: statement
	| statement_list statement
	;
     
expression_statement
	: ';'
	| expression ';'
	;

selection_statement
	: IF '(' expression ')' statement
	| IF '(' expression ')' statement ELSE statement
	| SWITCH '(' expression ')' statement
	;

iteration_statement
	: WHILE '(' expression ')' statement
	| DO statement WHILE '(' expression ')' ';'
	| FOR '(' expression_statement expression_statement ')' statement
	| FOR '(' expression_statement expression_statement expression ')' statement
	;

jump_statement
	: GOTO IDENTIFIER ';'
	| CONTINUE ';'
	| BREAK ';'
	| RETURN ';'
	| RETURN expression ';'
	;        

expression
	: assignment_expression
	| expression ',' assignment_expression
	;
	
assignment_expression
	: conditional_expression
	| unary_expression assignment_operator assignment_expression
	;
	
assignment_operator
	: '='
	| '*='
	| '/='
	| '%='
	| '+='
	| '-='
	| '<<='
	| '>>='
	| '&='
	| '^='
	| '|='
	;

constant_expression
	: conditional_expression
	;

conditional_expression
	: logical_or_expression
	| logical_or_expression '?' expression ':' conditional_expression
	;

logical_or_expression
	: logical_and_expression
	| logical_or_expression '||' logical_and_expression
	;

logical_and_expression
	: inclusive_or_expression
	| logical_and_expression '&&' inclusive_or_expression
	;

inclusive_or_expression
	: exclusive_or_expression
	| inclusive_or_expression '|' exclusive_or_expression
	;

exclusive_or_expression
	: and_expression
	| exclusive_or_expression '^' and_expression
	;

and_expression
	: equality_expression
	| and_expression '&' equality_expression
	;

equality_expression
	: relational_expression
	| equality_expression '==' relational_expression
	| equality_expression '!=' relational_expression
	;

relational_expression
	: shift_expression
	| relational_expression '<' shift_expression
	| relational_expression '>' shift_expression
	| relational_expression '<=' shift_expression
	| relational_expression '>=' shift_expression
	;

shift_expression
	: additive_expression
	| shift_expression '<<' additive_expression
	| shift_expression '>>' additive_expression
	;

additive_expression
	: multiplicative_expression
	| additive_expression '+' multiplicative_expression
	| additive_expression '-' multiplicative_expression
	;

multiplicative_expression
	: cast_expression
	| multiplicative_expression '*' cast_expression
	| multiplicative_expression '/' cast_expression
	| multiplicative_expression '%' cast_expression
	;

cast_expression
	: unary_expression
	| '(' type_name ')' cast_expression
	;
	
unary_expression
	: postfix_expression
	| '++' unary_expression
	| '--' unary_expression
	| unary_operator cast_expression
	| SIZEOF unary_expression
	| SIZEOF '(' type_name ')'
	;
	
unary_operator
	: '&'
	| '*'
	| '+'
	| '-'
	| '~'
	| '!'
	;
	
argument_expression_list
	: assignment_expression
	| argument_expression_list ',' assignment_expression
	;

postfix_expression
	: primary_expression
	| postfix_expression '[' expression ']'
	| postfix_expression '(' ')'
	| postfix_expression '(' argument_expression_list ')'
	| postfix_expression '.' IDENTIFIER
	| postfix_expression '->' IDENTIFIER
	| postfix_expression '++'
	| postfix_expression '--'
	;
	
primary_expression
	: IDENTIFIER
	| CONSTANT
	| STRING_LITERAL
	| '(' expression ')'
	;
%%