How to match a string, but case-insensitively?

Question

Let\'s say that I want to match \"beer\", but don\'t care about case sensitivity.

Currently I am defining a token to be (\'b\'|\'B\' \'e\'|\'E\' \'e\'|\'E\' \'r\'|

Answer 1

How about define a lexer token for each permissible identifier character, then construct the parser token as a series of those?

beer: B E E R;

A : 'A'|'a';
B: 'B'|'b';

etc.