function(type, token) {
    this.sets[type] = this.sets[type] || [];
    this.count++;
    this.stack.push(token);
    return this.sets[type].push(token);
  }
function(type, token) {
    this.sets[type] = this.sets[type] || [];
    this.count++;
    this.stack.push(token);
    return this.sets[type].push(token);
  }
function ( type , token ) { this . sets [ type ] = this . sets [ type ] || [ ] ; this . count ++ ; this . stack . push ( token ) ; return this . sets [ type ] . push ( token ) ; }
Push a `token` onto the `type` stack.

@param {String} `type`
@return {Object} `token`
@api public
Push a token onto the type stack .