Execute the lexer action in the context of the specified {@link Lexer}.
<p>For position-dependent actions, the input stream must already be positioned correctly prior to calling this method.</p>
@param lexer The lexer instance.
See Implementation
Execute the lexer action in the context of the specified {@link Lexer}.
<p>For position-dependent actions, the input stream must already be positioned correctly prior to calling this method.</p>
@param lexer The lexer instance.