lib/parser.js
function(n){
    var val = this.lookahead(n).val;
    return val && ~pseudoSelectors.indexOf(val.name);
  }
function(n){
    var val = this.lookahead(n).val;
    return val && ~pseudoSelectors.indexOf(val.name);
  }
function ( n ) { var val = this . lookahead ( n ) . val ; return val && ~ pseudoSelectors . indexOf ( val . name ) ; }
Check if the token at `n` is a pseudo selector.

@param {Number} n
@return {Boolean}
@api private
Check if the token at n is a pseudo selector .