findFunctionScoped(name) {
    if (this.vars[name]) {
      return this.vars[name];
    }
    if (this.parent) {
      return this.parent.findFunctionScoped(name);
    }
    return [];
  }
Looks up variables from function scope.
(Either from this function scope or from any parent function scope.)

@param  {String} name Variable name
@return {Variable[]} The found variables (empty array if none found)