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|
# This improved version of the C grammar was provided by Joe Buehler
use Parse::RecDescent;
local $/;
my $grammar = <DATA>;
my $parser = Parse::RecDescent->new($grammar);
my $text = <>;
my $parse_tree = $parser->translation_unit($text) or die "bad C code";
use Data::Dumper 'Dumper';
warn Dumper [ $parse_tree ];
__DATA__
<autotree>
primary_expression:
IDENTIFIER
| CONSTANT
| STRING_LITERAL
| '(' expression ')'
postfix_expression_post:
'[' expression ']'
| '(' argument_expression_list(?) ')'
| '.' IDENTIFIER
| '->' IDENTIFIER
| '++'
| '--'
postfix_expression:
primary_expression postfix_expression_post(s?)
argument_expression_list:
assignment_expression (',' assignment_expression)(s?)
unary_expression:
postfix_expression
| '++' unary_expression
| '--' unary_expression
| unary_operator cast_expression
| SIZEOF unary_expression
| SIZEOF '(' type_name ')'
unary_operator:
/[-&*+!~]/
cast_expression:
'(' type_name ')' cast_expression
| unary_expression
multiplicative_expression_op:
/[*\/%]/
multiplicative_expression:
cast_expression (multiplicative_expression_op cast_expression)(s?)
additive_expression_op:
/[-+]/
additive_expression:
multiplicative_expression (additive_expression_op multiplicative_expression)(s?)
shift_expression_pre_op:
/(<<|>>)(?!=)/
shift_expression:
additive_expression (shift_expression_pre_op additive_expression)(s?)
relational_expression_op:
/(<=|>=|<|>)/
relational_expression:
shift_expression (relational_expression_op shift_expression)(s?)
equality_expression_pre_op:
/==|!=/
equality_expression:
relational_expression (equality_expression_pre_op relational_expression)(s?)
and_expression:
equality_expression ('&' equality_expression)(s?)
exclusive_or_expression:
and_expression ('^' and_expression)(s?)
inclusive_or_expression:
exclusive_or_expression ('|' exclusive_or_expression)(s?)
logical_and_expression:
inclusive_or_expression ('&&' inclusive_or_expression)(s?)
logical_or_expression:
logical_and_expression ('||' logical_and_expression)(s?)
conditional_expression:
logical_or_expression ('?' expression ':' conditional_expression)(?)
assignment_expression:
conditional_expression
| unary_expression assignment_operator assignment_expression
assignment_operator:
/=(?!=)|\+=|\&=|\/=|<<=|\%=|\*=|\|=|>>=|-=|\^=/
expression:
assignment_expression (',' assignment_expression)(s?)
constant_expression:
conditional_expression
declaration:
declaration_specifiers init_declarator_list ';'
| declaration_specifiers ';'
declaration_specifiers:
( storage_class_specifier | type_specifier | type_qualifier )(s)
init_declarator_list:
init_declarator (',' init_declarator)(s?)
init_declarator:
declarator '=' initializer
| declarator
storage_class_specifier:
/(typedef|extern|static|auto|register)(?![a-zA-Z0-9_])/
type_specifier:
/(void|char|short|int|long|float|double|signed|unsigned)(?![a-zA-Z0-9_])/
| 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)(?![a-zA-Z0-9_])/
struct_declaration_list:
struct_declaration(s)
struct_declaration:
specifier_qualifier_list struct_declarator_list ';'
specifier_qualifier_list:
( type_specifier | type_qualifier )(s)
struct_declarator_list:
struct_declarator (',' struct_declarator)(s?)
struct_declarator:
declarator ':' constant_expression
| declarator
| ':' constant_expression
enum_specifier:
ENUM '{' enumerator_list '}'
| ENUM IDENTIFIER '{' enumerator_list '}'
| ENUM IDENTIFIER
enumerator_list:
enumerator (',' enumerator)(s?)
enumerator:
IDENTIFIER '=' constant_expression
| IDENTIFIER
type_qualifier:
/(const|volatile)(?![a-zA-Z0-9_])/
declarator:
pointer(?) direct_declarator
direct_declarator_pre:
IDENTIFIER
| '(' declarator ')'
direct_declarator_post:
'[' constant_expression ']'
| '[' ']'
| '(' parameter_type_list ')'
| '(' identifier_list ')'
| '(' ')'
direct_declarator:
direct_declarator_pre direct_declarator_post(s?)
pointer:
'*' type_qualifier_list(?) pointer(?)
type_qualifier_list:
type_qualifier(s)
parameter_type_list:
parameter_list ',' '...'
| parameter_list
parameter_list:
parameter_declaration (',' parameter_declaration)(s?)
parameter_declaration:
declaration_specifiers declarator
| declaration_specifiers abstract_declarator(?)
identifier_list:
IDENTIFIER (',' IDENTIFIER)(s?)
type_name:
specifier_qualifier_list abstract_declarator(?)
abstract_declarator:
pointer direct_abstract_declarator(?)
| direct_abstract_declarator
direct_abstract_declarator_pre:
'(' abstract_declarator ')'
| direct_abstract_declarator_post
direct_abstract_declarator_post:
'[' ']'
| '[' constant_expression ']'
| '(' ')'
| '(' parameter_type_list ')'
direct_abstract_declarator:
direct_abstract_declarator_pre direct_abstract_declarator_post(s?)
initializer:
assignment_expression
| '{' initializer_list '}'
| '{' initializer_list ',' '}'
initializer_list:
initializer (',' initializer)(s?)
statement:
labeled_statement
| compound_statement
| expression_statement
| selection_statement
| iteration_statement
| jump_statement
labeled_statement:
IDENTIFIER ':' statement
| /case(?![a-zA-Z0-9_])/ constant_expression ':' statement
| /default(?![a-zA-Z0-9_])/ ':' statement
compound_statement:
'{' declaration_list statement_list(?) '}'
| '{' statement_list(?) '}'
declaration_list:
declaration(s)
statement_list:
statement(s)
expression_statement:
expression(?) ';'
selection_statement:
IF '(' expression ')' statement ELSE statement
| IF '(' expression ')' statement
| SWITCH '(' expression ')' statement
iteration_statement:
WHILE '(' expression ')' statement
| DO statement WHILE '(' expression ')' ';'
| FOR '(' expression_statement expression_statement expression(?) ')' statement
jump_statement:
/goto(?![a-zA-Z0-9_])/ IDENTIFIER ';'
| /continue(?![a-zA-Z0-9_])/ ';'
| /break(?![a-zA-Z0-9_])/ ';'
| /return(?![a-zA-Z0-9_])/ expression(?) ';'
translation_unit:
external_declaration(s)
external_declaration:
function_definition { print "*** function\n"; }
| declaration { print "*** declaration\n"; }
function_definition:
declaration_specifiers declarator(?) declaration_list(?) compound_statement
reserved_word:
/(auto|break|case|char|const|continue|default|do|double|enum|extern|float|for|goto|if|int|long|register|return|short|signed|sizeof|static|struct|switch|typedef|union|unsigned|void|volatile|while)(?![a-zA-Z0-9_])/
CONSTANT: /[+-]?(?=\d|\.\d)\d*(\.\d*)?([Ee]([+-]?\d+))?/
DO: /do(?![a-zA-Z0-9_])/
ELSE: /else(?![a-zA-Z0-9_])/
ENUM: /enum(?![a-zA-Z0-9_])/
FOR: /for(?![a-zA-Z0-9_])/
IDENTIFIER: ...!reserved_word /[a-zA-Z_][a-zA-Z_0-9]*/
IF: /if(?![a-zA-Z0-9_])/
SIZEOF: /sizeof(?![a-zA-Z0-9_])/
STRING_LITERAL: { extract_delimited($text,'"') }
SWITCH: /switch(?![a-zA-Z0-9_])/
TYPE_NAME: ...!reserved_word /[a-zA-Z_][a-zA-Z_0-9]*/ ...IDENTIFIER
| ...!reserved_word /[a-zA-Z_][a-zA-Z_0-9]*/ .../[:*)]/
WHILE: /while(?![a-zA-Z0-9_])/
|
