39 lines
564 B
Plaintext
39 lines
564 B
Plaintext
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/* description: Parses end executes mathematical expressions. */
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%left '+' '-'
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%left '*' '/'
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%left '^'
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%left UMINUS
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%%
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S
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: e EOF
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{print($1); return $1;}
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;
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e
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: e '+' e
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{$$ = $1+$3;}
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| e '-' e
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{$$ = $1-$3;}
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| e '*' e
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{$$ = $1*$3;}
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| e '/' e
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{$$ = $1/$3;}
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| e '^' e
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{$$ = Math.pow($1, $3);}
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| '-' e %prec UMINUS
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{$$ = -$2;}
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| '(' e ')'
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{$$ = $2;}
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| NUMBER
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{$$ = Number(yytext);}
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| E
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{$$ = Math.E;}
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| PI
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{$$ = Math.PI;}
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;
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