Yacc rogram Post: 302747425

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Top Forums Programming Yacc rogram Post 302747425 by zolafencer on Friday 21st of December 2012 03:14:20 PM

12-21-2012

Registered User

Yacc rogram

hello, actually i want to generate rgram in yacc able to do do several operations separated by ';' and after show all the results separated by ';' again.
My code do just one operations and i couldn' t find solution to do several ones separated by ';'. I thought may be i can do a do... while but i don't know how to do it for my example. If someone can help me please.
here is my .y for just one operation

Code:

%{ double vbltable[26]; %}

%union {
       double dval ;
       int vblno; }

%token <vblno> NAME 
%token <dval>  NUMBER

%type  <dval> expression

%%
statement_list:  
  statement '\n'
| statement_list statement '\n'
;

statement: 
  NAME '=' expression { vbltable[$1] = $3; }
| expression          { printf("est %g\n", $1); }
;

expression: 
  expression expression '+' { $$ = $1 + $2; }
| expression expression '-' { $$ = $1 - $2; }
| expression expression '*' { $$ = $1 * $2; }
| expression expression '/' {if($2 == 0.0)
                             printf("erreur ! Division par 0");
                             else
                             $$ = $1 / $2; }
| '(' '-' expression ')'    { $$ = -$3; }
| NUMBER                    { $$ = $1; }
| NAME                      { $$ = vbltable[$1]; }
;
%%

int yyerror() { printf("erreur") ; } 
int main () { yyparse(); }

and here is my .l

Code:

%{ 
#include "y.tab.h" 
#include <math.h>
extern double vbltable[26];
%}

%%

([0-9]+|([0-9]*"."[0-9]+)) { yylval.dval = atof(yytext); return NUMBER; }
\t;                        { ; }
" "                        { ; }
[a-z]                      { yylval.vblno = yytext[0] - 'a' ; return NAME;}
"$"                        { return 0; 
                             /* symb. de retour pour fin de fichier */}
\n                         { return yytext[0]; }
.                          { return yytext[0]; }

%%

thanks

---------- Post updated at 03:14 PM ---------- Previous update was at 09:06 AM ----------

no answer?? come on it's christmas soon Smilie

Last edited by joeyg; 12-21-2012 at 10:08 AM.. Reason: Please wrap commands and data with CodeTags

zolafencer

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ausearch_add_expression

AUSEARCH_ADD_expression(3)					  Linux Audit API					AUSEARCH_ADD_expression(3)

NAME

       ausearch_add_expression - build up search expression

SYNOPSIS

       #include <auparse.h>

       int ausearch_add_expression(auparse_state_t *au, const char *expression, char **error, ausearch_rule_t how);

DESCRIPTION

       ausearch_add_item  adds	an expression to the current audit search expression.  The search conditions can then be used to scan logs, files,
       or buffers for something of interest.  The expression parameter contains an expression, as specified in ausearch-expression(5).

       The how parameter determines how this search expression will affect the existing search expression, if one is already defined.  The  possi-
       ble values are:

	      AUSEARCH_RULE_CLEAR
		     Clear the current search expression, if any, and use only this search expression.

	      AUSEARCH_RULE_OR
		     If a search expression E is already configured, replace it by (E || this_search_expression).

	      AUSEARCH_RULE_AND
		     If a search expression E is already configured, replace it by (E && this_search_expression).

RETURN VALUE

       If  successful,	ausearch_add_expression  returns  0.   Otherwise, it returns -1, sets errno and it may set *error to an error message; the
       caller must free the error message using free(3).  If an error message is not available or can not be allocated, *error is set to NULL.

SEE ALSO

       ausearch_add_item(3), ausearch_add_interpreted_item(3), ausearch_add_timestamp_item(3), ausearch_add_regex(3), ausearch_set_stop(3),  ause-
       arch_clear(3), ausearch_next_event(3), ausearch-expression(5).

AUTHOR

       Miloslav Trmac

Red Hat 							     Feb 2008						AUSEARCH_ADD_expression(3)