C99 Language syntax summary
/*
=========================================================
Name : C99 sntax.txt
Author : luqi
Version :
Copyright : Your copyright notice
Description : C99 Language syntax summary
==========================================================
*/
/**************************************************************************
Lexical grammar
**************************************************************************/
token:
keyword // 关键字
identifier // 标识符
constant // 常量
string_literal // 字符串字面值
punctuator // 标点符号(算符)
/*
* Keywords
*/
keyword:
auto break case char const continue
default do double else enum extern
float for goto if inline int
long register restrict return short signed
sizeof static struct switch typedef union
unsigned void volatile while _Bool _Complex
_Imaginary
/*
* Identifiers
* /
identifier:
identifier_nondigit
identifier identifier_nondigit
identifier digit
identifier_nondigit:
nondigit
universal_character_name // C99 新增
other implementation_defined characters // C99 新增
nondigit:
a-z
A-Z
_
digit:
0-9
/*
* Universal character names
*/
universal_character_name:
\u hex_quad
\U hex_quad hex_quad
hex_quad:
hexadecimal_digit hexadecimal_digit hexadecimal_digit hexadecimal_digit
/*
* Constants
*/
constant:
integer_constant
floating_constant
enumeration_constant
character_constant
//***integer_constant
integer_constant:
decimal_constant integer_suffix ?
octal_constant integer_suffix ?
hexadecimal_constant integer_suffix ?
integer_suffix:
unsigned_suffix long_suffix ?
unsigned_suffix long_long_suffix
long_suffix unsigned_suffix ?
long_long_suffix unsigned_suffix ?
unsigned_suffix:
u
U
long_suffix: one of
l
L
long_long_suffix: one of
ll
LL
decimal_constant:
nonzero_digit
decimal_constant digit
octal_constant:
0
octal_constant octal_digit
hexadecimal_constant:
hexadecimal_prefix hexadecimal_digit
hexadecimal_constant hexadecimal_digit
hexadecimal_prefix:
0x
0X
nonzero_digit:
1-9
octal_digit:
0-7
hexadecimal_digit:
0-9
a-f
A-F
//***floating_constant
floating_constant:
decimal_floating_constant
hexadecimal_floating_constant
decimal_floating_constant:
fractional_constant exponent_part ? floating_suffix ?
digit_sequence exponent_part floating_suffix ?
fractional_constant:
digit_sequence ? . digit_sequence
digit_sequence .
exponent_part:
e sign ? digit_sequence
E sign ? digit_sequence
sign:
+
-
digit_sequence:
digit
digit_sequence digit
hexadecimal_floating_constant:
hexadecimal_prefix hexadecimal_fractional_constant binary_exponent_part floating_suffix ?
hexadecimal_prefix hexadecimal_digit_sequence binary_exponent_part floating_suffix ?
hexadecimal_fractional_constant:
hexadecimal_digit_sequence ? . hexadecimal_digit_sequence
hexadecimal_digit_sequence .
binary_exponent_part:
p sign ? digit_sequence
P sign ? digit_sequence
hexadecimal_digit_sequence:
hexadecimal_digit
hexadecimal_digit_sequence hexadecimal_digit
floating_suffix:
f
l
F
L
//***enumeration_constant
enumeration_constant:
identifier
//***character_constant
character_constant:
' c_char_sequence '
L' c_char_sequence '
c_char_sequence:
c_char
c_char_sequence c_char
c_char:
any member of the source character set except the single_quote ', backslash \, or new_line character
escape_sequence
escape_sequence:
simple_escape_sequence
octal_escape_sequence
hexadecimal_escape_sequence
universal_character_name
simple_escape_sequence:
\' \" \? \\ \a
\b \f \n \r \t \v
octal_escape_sequence:
\ octal_digit
\ octal_digit octal_digit
\ octal_digit octal_digit octal_digit
hexadecimal_escape_sequence:
\x hexadecimal_digit
hexadecimal_escape_sequence hexadecimal_digit
/*
* String literals
*/
string_literal:
" s_char_sequence ? "
L" s_char_sequence ? "
s_char_sequence:
s_char
s_char_sequence s_char
s_char:
any member of the source character set except the double_quote ", backslash \, or new_line character
escape_sequence
/*
* Punctuators
*/
punctuator:
[ ] ( ) { } . ->
++ -- & * + - ~ !
/ % << >> < > <= > == = != ^ | && ||
? : ; ...
= *= /= %= += -= <<= >>= &= ^= |=
, # ##
<: :> <% %> %: %:%:
/**************************************************************************
Phrase structure grammar
**************************************************************************/
/**
* Expressions
*/
primary_expression:
identifier
constant
string_literal
( expression )
/**
* 后缀表达式,优先级最高
*/
postfix_expression:
primary_expression // exp
postfix_expression [ expression ] // exp[], exp[pxe]
postfix_expression ( argument_expression_list ? ) // exp(), exp[pxe1,pxe2,pxe3]
postfix_expression . identifier // exp.idn
postfix_expression -> identifier // exp->idn
postfix_expression ++ // exp++
postfix_expression -- // exp--
( type_name ){ initializer_list } // fifi // (int *){1, 2, 3} C99 新增
( type_name ){ initializer_list ,} // fifi // (int *){1, 2, 3,} C99 新增 字面值常量
argument_expression_list:
assignment_expression
argument_expression_list , assignment_expression
unary_expression:
postfix_expression
++ unary_expression
-- unary_expression
unary_operator cast_expression
sizeof unary_expression
sizeof ( type_name )
unary_operator:
& * + - ~ !
cast_expression:
unary_expression
( type_name ) cast_expression
multiplicative_expression:
cast_expression
multiplicative_expression * cast_expression
multiplicative_expression / cast_expression
multiplicative_expression % cast_expression
additive_expression:
multiplicative_expression
additive_expression + multiplicative_expression
additive_expression - multiplicative_expression
shift_expression:
additive_expression
shift_expression << additive_expression
shift_expression >> additive_expression
relational_expression:
shift_expression
relational_expression < shift_expression
relational_expression > shift_expression
relational_expression <= shift_expression
relational_expression >= shift_expression
equality_expression:
relational_expression
equality_expression == relational_expression
equality_expression != relational_expression
AND-expression:
equality_expression
AND-expression & equality_expression
exclusive-OR-expression:
AND-expression
exclusive-OR-expression ^ AND-expression
inclusive-OR-expression:
exclusive-OR-expression
inclusive-OR-expression | exclusive-OR-expression
logical-AND-expression:
inclusive-OR-expression
logical-AND-expression && inclusive-OR-expression
logical-OR-expression:
logical-AND-expression
logical-OR-expression || logical-AND-expression
conditional_expression:
logical-OR-expression
logical-OR-expression fi expression : conditional_expression
assignment_expression:
conditional_expression
unary_expression assignment_operator assignment_expression
assignment_operator: one of
= *= /= %= += -= <<= >>= &= ^= |=
expression:
assignment_expression
expression , assignment_expression
constant_expression: //
conditional_expression
/**************************************************************************
Declarations
**************************************************************************/
declaration:
declaration_specifiers init_declarator_list ? ;
declaration_specifiers:
storage_class_specifier declaration_specifiers ?
type_specifier declaration_specifiers ?
type_qualifier declaration_specifiers ?
function_specifier declaration_specifiers ?
init_declarator_list:
init_declarator
init_declarator_list , init_declarator
init_declarator:
declarator
declarator = initializer
storage_class_specifier:
typedef
extern
static
auto
register
type_specifier:
void
char
short
int
long
float
double
signed
unsigned
_Bool
_Complex
_Imaginary
struct_or_union_specifier
enum_specifier
typedef_name
struct_or_union_specifier:
struct_or_union identifier ? { 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 ;
specifier_qualifier_list:
type_specifier specifier_qualifier_list ?
type_qualifier specifier_qualifier_list ?
struct_declarator_list:
struct_declarator
struct_declarator_list , struct_declarator
struct_declarator:
declarator
declarator ? : constant_expression
enum_specifier:
enum identifier ? { enumerator_list }
enum identifier ? { enumerator_list ,}
enum identifier
enumerator_list:
enumerator
enumerator_list , enumerator
enumerator:
enumeration_constant
enumeration_constant = constant_expression
type_qualifier:
const
restrict
volatile
function_specifier:
inline
declarator:
pointer ? direct_declarator
direct_declarator:
identifier
( declarator )
direct_declarator [ type_qualifier_list ? assignment_expression ? ]
direct_declarator [ static type_qualifier_list ? assignment_expression ]
direct_declarator [ type_qualifier_list static assignment_expression ]
direct_declarator [ type_qualifier_list ? *]
direct_declarator ( parameter_type_list )
direct_declarator ( identifier_list ? )
pointer:
* type_qualifier_list ?
* type_qualifier_list ? pointer
type_qualifier_list:
type_qualifier
type_qualifier_list type_qualifier
parameter_type_list:
parameter_list
parameter_list , ...
parameter_list:
parameter_declaration
parameter_list , parameter_declaration
parameter_declaration:
declaration_specifiers declarator
declaration_specifiers abstract_declarator ?
identifier_list:
identifier
identifier_list , identifier
type_name: // fi
specifier_qualifier_list abstract_declarator ?
abstract_declarator:
pointer
pointer ? direct_abstract_declarator
direct_abstract_declarator:
( abstract_declarator )
direct_abstract_declarator ? [ assignment_expression ? ]
direct_abstract_declarator ? [*]
direct_abstract_declarator ? ( parameter_type_list ? )
typedef_name: // fi
identifier
initializer: // fi
assignment_expression
{ initializer_list }
{ initializer_list ,}
initializer_list:
designation ? initializer
initializer_list , designation ? initializer
designation:
designator_list =
designator_list:
designator
designator_list designator
designator:
[ constant_expression ]
. identifier
/**************************************************************************
Statements
**************************************************************************/
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:
{ block_item_list ? }
block_item_list:
block_item
block_item_list block_item
block_item:
declaration
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 ? ; expression ? ; expression ? ) statement
for ( declaration expression ? ; expression ? ) statement
jump_statement:
goto identifier ;
continue ;
break ;
return expression ? ;
/**************************************************************************
External definitions
**************************************************************************/
translation_unit:
external_declaration
translation_unit external_declaration
external_declaration:
function_definition
declaration
function_definition:
declaration_specifiers declarator declaration_list ? compound_statement
declaration_list:
declaration
declaration_list declaration