36 lines
619 B
Plaintext
36 lines
619 B
Plaintext
/*
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* expr.lex : Scanner for a simple
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* expression parser.
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*/
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%{
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#include "y.tab.h"
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%}
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%%
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[0-9]+ { yylval.val = atol(yytext);
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return(NUMBER);
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}
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[0-9]+\.[0-9]+ {
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sscanf(yytext,"%f",&yylval.val);
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return(NUMBER);
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}
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"+" return(PLUS);
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"-" return(MINUS);
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"*" return(MULT);
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"/" return(DIV);
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"^" return(EXPON);
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"(" return(LB);
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")" return(RB);
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\n return(EOL);
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[\t ]* /* throw away whitespace */
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. { yyerror("Illegal character");
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return(EOL);
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}
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%%
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