Hello... I want to ask you a question about Flex, the program for parsing code. Supposing I have an instruction like this one, in the rules part: "=" BEGIN(attribution); <attribution>{var_name} { fprintf(yyout, "="); ECHO; } <attribution>";" BEGIN(INITIAL); {var_name} is a regular expression that matches a variable's name, and all I want to do is to copy at the output all the attribution instructions, such as a = 3; or b = a; My rule though cannot write with fprintf the left member of the attribution, but only = 3; or =a; One solution for that might be that, after I make the match "=" and I am in the attribution state, to go 2 positions back as to get the left operand as well. How can I do that in Flex?