required packages for lex and yacc files
 

what are the packages required to run or compile lex and yacc files on ubuntu?
how they are used?
what are there purpose?

Welcome to LQ.

Installing a lexer and a parser : sudo apt-get install flex bison
... Will provide /usr/bin/flex , /usr/bin/bison.yacc .
http://packages.ubuntu.com/oneiric/flex
http://packages.ubuntu.com/oneiric/bison


And please use Google .. what is a lexer ..
http://en.wikipedia.org/wiki/Lex_%28software%29

Google .. what is a parser ..
http://en.wikipedia.org/wiki/Parsing
> http://en.wikipedia.org/wiki/GNU_bison

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