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Flex / bison error: undeclared

Hello, I have a problem, the following program returns an error, error :: Undeclared (first use in a function), why this error appears, all tokens are declared, but this error occurs, can someone help me, here are the lex and yac.thanks files

Lexa:

%{
int yylinenu= 1;
int yycolno= 1;
%}

%x STR
DIGIT                     [0-9]
ALPHA                     [a-zA-Z]
ID                        {ALPHA}(_?({ALPHA}|{DIGIT}))*_?
GROUPED_NUMBER        ({DIGIT}{1,3})(\.{DIGIT}{3})*
SIMPLE_NUMBER             {DIGIT}+
NUMMER                {GROUPED_NUMBER}|{SIMPLE_NUMBER}
%%
<INITIAL>{
[\n]                      {++yylinenu ; yycolno=1;} 
[ ]+                      {yycolno=yycolno+yyleng;} 
[\t]+             {yycolno=yycolno+(yyleng*8);} 
"*"                       {return MAL;}
"+"                       {return PLUS;}
"-"                       {return MINUS;}
"/"                       {return SLASH;}
"("                       {return LINKEKLAMMER;}
")"                       {return RECHTEKLAMMER;}
"{"                       {return LINKEGESCHWEIFTEKLAMMER;}
"}"                       {return RECHTEGESCHEIFTEKLAMMER;}
"="                       {return GLEICH;}
"=="                      {return GLEICHVERGLEICH;}
"!="                      {return UNGLEICH;}
"<"                       {return KLEINER;}
">"                       {return GROSSER;}
"<="                      {return KLEINERGLEICH;}
">="                      {return GROSSERGLEICH;}
"while"                   {return WHILE;}
"if"                      {return IF;}
"else"                    {return ELSE;}
"printf"                  {return PRINTF;}
";"                       {return SEMIKOLON;}  
\/\/[^\n]*                { ;}
{NUMMER}                  {return NUMBER;}
{ID}                      {return IDENTIFIER;}
\"                {BEGIN(STR);}                  
.                         {;} 
}

<STR>{ 
\n                        {++yylinenu ;yycolno=1;} 
([^\"\\]|"\\t"|"\\n"|"\\r"|"\\b"|"\\\"")+        {return STRING;}
\"                                             {BEGIN(INITIAL);}
}
%%
yywrap()
{
}

YACC:

%{
#include stdio.h>
#include string.h>
#include "lex.yy.c"

void yyerror(char *err);
int error=0,linecnt=1;
%}

%token IDENTIFIER NUMBER STRING COMMENT PLUS MINUS MAL SLASH LINKEKLAMMER RECHTEKLAMMER LINKEGESCHWEIFTEKLAMMER RECHTEGESCHEIFTEKLAMMER GLEICH GLEICHVERGLEICH UNGLEICH GROSSER KLEINER GROSSERGLEICH KLEINERGLEICH IF ELSE WHILE PRINTF SEMIKOLON


%start Stmts

%%
Stmts : Stmt
{puts("\t\tStmts : Stmt");}
|Stmt Stmts
{puts("\t\tStmts : Stmt Stmts");}
; //NEUE REGEL----------------------------------------------
Stmt : LINKEGESCHWEIFTEKLAMMER Stmts RECHTEGESCHEIFTEKLAMMER
{puts("\t\tStmt : '{' Stmts '}'");}
|IF LINKEKLAMMER Cond RECHTEKLAMMER Stmt
{puts("\t\tStmt : '(' Cond ')' Stmt");}
|IF LINKEKLAMMER Cond RECHTEKLAMMER Stmt  ELSE Stmt
{puts("\t\tStmt : '(' Cond ')' Stmt 'ELSE' Stmt");}
|WHILE LINKEKLAMMER Cond RECHTEKLAMMER Stmt
{puts("\t\tStmt : 'PRINTF' Expr ';'");}
|PRINTF Expr SEMIKOLON
{puts("\t\tStmt : 'PRINTF' Expr ';'");}
|IDENTIFIER GLEICH Expr SEMIKOLON
{puts("\t\tStmt : 'IDENTIFIER' '=' Expr ';'");}
|SEMIKOLON
{puts("\t\tStmt : ';'");}
;//NEUE REGEL ---------------------------------------------
Cond: Expr GLEICHVERGLEICH Expr 
{puts("\t\tCond : '==' Expr");}
|Expr UNGLEICH Expr
{puts("\t\tCond : '!=' Expr");}
|Expr KLEINER Expr
{puts("\t\tCond : '<' Expr");}
|Expr KLEINERGLEICH Expr
{puts("\t\tCond : '<=' Expr");}
|Expr GROSSER Expr
{puts("\t\tCond : '>' Expr");}
|Expr GROSSERGLEICH Expr
{puts("\t\tCond : '>=' Expr");}
;//NEUE REGEL --------------------------------------------
Expr:Term 
{puts("\t\tExpr : Term");}
|Term PLUS Expr 
{puts("\t\tExpr : Term '+' Expr");}
|Term MINUS Expr 
{puts("\t\tExpr : Term '-' Expr");}
;//NEUE REGEL --------------------------------------------
Term:Factor
{puts("\t\tTerm : Factor");}
|Factor MAL Term
{puts("\t\tTerm : Factor '*' Term");}
|Factor SLASH Term
{puts("\t\tTerm : Factor '/' Term");}
;//NEUE REGEL --------------------------------------------
Factor:SimpleExpr
{puts("\t\tFactor : SimpleExpr");}
|MINUS SimpleExpr
{puts("\t\tFactor : '-' SimpleExpr");}
;//NEUE REGEL --------------------------------------------
SimpleExpr:LINKEKLAMMER Expr RECHTEKLAMMER
{puts("\t\tSimpleExpr : '(' Expr ')'");}
|IDENTIFIER
{puts("\t\tSimpleExpr : 'IDENTIFIER'");}
|NUMBER 
{puts("\t\tSimpleExpr : 'NUMBER'");}
|STRING
{puts("\t\tSimpleExpr : 'String'");}
;//ENDE -------------------------------------------------
%%
void yyerror(char *msg)
{
 error=1;
 printf("Line: %d , Column: %d : %s \n", yylinenu, yycolno,yytext, msg); 
}
int main(int argc, char *argv[])
{

        int val;
        while(yylex())  
        {       
         printf("\n",yytext);       
    }
    return yyparse();
}
+3
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2 answers

The main problem is that you are trying to include your lexer in your parser. What you (at least usually) want to do is have yacc (bison, if necessary) create a header (y.tab.h), using yacc -dand including this in your lexer.

Lexer start:

%{
#include "y.tab.h"
int yylinenu= 1;
int yycolno= 1;
%}
// ...

, , , :

extern int yylinenu;
extern int yycolno;

main() error() ( main() , , , , , ...).

void yyerror(char *msg)
{
    printf("Line: %d , Column: %d : %s \n", yylinenu, yycolno, msg); 
}

int main(int argc, char *argv[])
{
    return yyparse();
}

, , , , , . :

|WHILE LINKEKLAMMER Cond RECHTEKLAMMER Stmt 
    {puts("\t\tStmt : 'PRINTF' Expr ';'");}
|PRINTF Expr SEMIKOLON  
    {puts("\t\tStmt : 'PRINTF' Expr ';'");}

, "while", "while", "printf":

|WHILE LINKEKLAMMER Cond RECHTEKLAMMER Stmt 
    {puts("\t\tStmt : 'WHILE' Expr ';'");}

, :

|IF LINKEKLAMMER Cond RECHTEKLAMMER Stmt    
    {puts("\t\tStmt : '(' Cond ')' Stmt");}
|IF LINKEKLAMMER Cond RECHTEKLAMMER Stmt  ELSE Stmt 
    {puts("\t\tStmt : '(' Cond ')' Stmt 'ELSE' Stmt");}

, , , "if" :

|IF LINKEKLAMMER Cond RECHTEKLAMMER Stmt    
    {puts("\t\tStmt : 'IF' '(' Cond ')' Stmt");}
|IF LINKEKLAMMER Cond RECHTEKLAMMER Stmt  ELSE Stmt 
    {puts("\t\tStmt : 'IF' '(' Cond ')' Stmt 'ELSE' Stmt");}

, :

Term:Factor                 {puts("\t\tTerm : Factor");}
    | Factor MAL Term       {puts("\t\tTerm : Factor '*' Term");}
    | Factor SLASH Term     {puts("\t\tTerm : Factor '/' Term");}
    ;

Factor:SimpleExpr           {puts("\t\tFactor : SimpleExpr");}
    | MINUS SimpleExpr      {puts("\t\tFactor : '-' SimpleExpr");}
    ;

, , , ( ), . , , , - .

: : (, bison/yacc/byacc generate) , :

Stmts : Stmt                {puts("\t\tStmts : Stmt");}
    | Stmt Stmts            {puts("\t\tStmts : Stmt Stmts");}
    ;

To:

Stmts : Stmt                {puts("\t\tStmts : Stmt");}
    | Stmts Stmt            {puts("\t\tStmts : Stmts Stmt");}
    ;
+3

, JMP L1.

:L1
IF FLAG AND X"0001"
EVT 23;
ELSE
WAIT 500 ms;
JMP L1;
END IF;

.

0

Source: https://habr.com/ru/post/1741753/

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