92 lines
1.1 KiB
Plaintext
92 lines
1.1 KiB
Plaintext
grammar t017parser;
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options {
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language = Python3;
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}
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program
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: declaration+
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;
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declaration
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: variable
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| functionHeader ';'
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| functionHeader block
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;
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variable
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: type declarator ';'
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;
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declarator
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: ID
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;
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functionHeader
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: type ID '(' ( formalParameter ( ',' formalParameter )* )? ')'
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;
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formalParameter
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: type declarator
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;
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type
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: 'int'
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| 'char'
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| 'void'
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| ID
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;
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block
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: '{'
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variable*
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stat*
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'}'
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;
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stat: forStat
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| expr ';'
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| block
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| assignStat ';'
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| ';'
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;
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forStat
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: 'for' '(' assignStat ';' expr ';' assignStat ')' block
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;
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assignStat
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: ID '=' expr
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;
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expr: condExpr
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;
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condExpr
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: aexpr ( ('==' | '<') aexpr )?
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;
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aexpr
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: atom ( '+' atom )*
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;
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atom
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: ID
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| INT
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| '(' expr ')'
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;
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ID : ('a'..'z'|'A'..'Z'|'_') ('a'..'z'|'A'..'Z'|'0'..'9'|'_')*
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;
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INT : ('0'..'9')+
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;
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WS : ( ' '
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| '\t'
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| '\r'
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| '\n'
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)+
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{$channel=HIDDEN}
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;
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