CODEWITHSUNDEEP
debuggingtypesocamlyaccreduce-reduce-conflict
Vivek Pradhan
Vivek Pradhan

Reputation: 4847

Conflicts in ocamlyacc

I am trying to write a parser for a simple language that recognizes integer and float expressions using ocamlyacc. However I want to introduce the possiblity of having variables. So i defined the token VAR in my lexer.mll file which allows it to be any alphanumneric string starting with a capital letter.

 expr:
 | INT                      { $1 }
 | VAR                      { /*Some action */}
 | expr PLUS expr           { $1 + $3 }
 | expr MINUS expr          { $1 - $3 }

 /* and similar rules below for real expressions differently */

Now i have a similar definition for real numbers. However when i run this file, I get 2 reduce/reduce conflict because if i just enter a random string(identified as token VAR). The parser would not know if its a real or an integer type of variable as the keyword VAR is present in defining both int and real expressions in my grammar.

Var + 12  /*means that Var has to be an integer variable*/
Var  /*Is a valid expression according to my grammar but can be of any type*/

How do I eliminate this reduce/reduce conflict without losing the generality of variable declaration and mainting the 2 data types available to me.

Upvotes: 0

Views: 202

Answers (0)

Related Questions