BNF de C
<translation-unit> ::= {<external-declaration>}*
<external-declaration> ::= <function-definition> | <declaration>
<function-definition> ::= {<declaration-specifier>}* <declarator> {<declaration>}* <compound-statement>
<declaration-specifier> ::= <storage-class-specifier> | <type-specifier> | <type-qualifier>
<storage-class-specifier> ::= auto | register | static | extern | typedef
<type-specifier> ::= void | char | short | int | long | float | double
| signed | unsigned | <struct-or-union-specifier>
| <enum-specifier> | <typedef-name>
<struct-or-union-specifier> ::= <struct-or-union> <identifier> { {<struct-declaration>}+ }
| <struct-or-union> { {<struct-declaration>}+ } | <struct-or-union> <identifier>
<struct-or-union> ::= struct | union
<struct-declaration> ::= {<specifier-qualifier>}* <struct-declarator-list>
<specifier-qualifier> ::= <type-specifier> | <type-qualifier>
<struct-declarator-list> ::= <struct-declarator> | <struct-declarator-list> , <struct-declarator>
<struct-declarator> ::= <declarator> | <declarator> : <constant-expression>
| : <constant-expression>
<declarator> ::= {<pointer>}? <direct-declarator>
<pointer> ::= * {<type-qualifier>}* {<pointer>}?
<type-qualifier> ::= const | volatile
<direct-declarator> ::= <identifier> | ( <declarator> ) | <direct-declarator> [ {<constant-expression>}? ]
| <direct-declarator> ( <parameter-type-list> ) | <direct-declarator> ( {<identifier>}* )
<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>
<postfix-expression> ::= <primary-expression>
| <postfix-expression> [ <expression> ]
| <postfix-expression> ( {<assignment-expression>}* )
| <postfix-expression> . <identifier>
| <postfix-expression> -> <identifier>
| <postfix-expression> ++
| <postfix-expression> --
<primary-expression> ::= <identifier> | <constant> | <string>
| ( <expression> )
<constant> ::= <integer-constant> | <character-constant>
| <floating-constant>
| <enumeration-constant>
<expression> ::= <assignment-expression>
| <expression> , <assignment-expression>
<assignment-expression> ::= <conditional-expression>
| <unary-expression> <assignment-operator> <assignment-expression>
<assignment-operator> ::= = | *= | /= | %= | += | -=
| <<= | >>= | &= | ^= | |=
<unary-operator> ::= & | * | + | - | ~ | !
<type-name> ::= {<specifier-qualifier>}+ {<abstract-declarator>}?
<parameter-type-list> ::= <parameter-list>
| <parameter-list> , ...
<parameter-list> ::= <parameter-declaration>
| <parameter-list> , <parameter-declaration>
<parameter-declaration> ::= {<declaration-specifier>}+ <declarator>
| {<declaration-specifier>}+ <abstract-declarator>
| {<declaration-specifier>}+
<abstract-declarator> ::= <pointer>
| <pointer> <direct-abstract-declarator>
| <direct-abstract-declarator>
<direct-abstract-declarator> ::= ( <abstract-declarator> )
| {<direct-abstract-declarator>}? [ {<constant-expression>}? ]
| {<direct-abstract-declarator>}? ( {<parameter-type-list>|? )
<enum-specifier> ::= enum <identifier> { <enumerator-list> }
| enum { <enumerator-list> }
| enum <identifier>
<enumerator-list> ::= <enumerator>
| <enumerator-list> , <enumerator>
<enumerator> ::= <identifier>
| <identifier> = <constant-expression>
<typedef-name> ::= <identifier>
<declaration> ::= {<declaration-specifier>}+ {<init-declarator>}*
<init-declarator> ::= <declarator>
| <declarator> = <initializer>
<initializer> ::= <assignment-expression>
| { <initializer-list> }
| { <initializer-list> , }
<initializer-list> ::= <initializer>
| <initializer-list> , <initializer>
<compound-statement> ::= { {<declaration>}* {<statement>}* }
<statement> ::= <labeled-statement>
| <expression-statement>
| <compound-statement>
| <selection-statement>
| <iteration-statement>
| <jump-statement>
<labeled-statement> ::= <identifier> : <statement>
| case <constant-expression> : <statement>
| default : <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>
<jump-statement> ::= goto <identifier> ;
| continue ;
| break ;
| return {<expression>}? ;
Fonte:
www.cs.wmich.edu/~gupta/teaching/cs4850/sumII06/The%20syntax%20of%20C%20in%20Backus-Naur%20form.htm