function acceptRequired(node, name) {
	    this.acceptKey(node, name);

	    if (!node[name]) {
	      throw new _exception2['default'](node.type + ' requires ' + name);
	    }
	  }
function acceptRequired(node, name) {
	    this.acceptKey(node, name);

	    if (!node[name]) {
	      throw new _exception2['default'](node.type + ' requires ' + name);
	    }
	  }
function acceptRequired ( node , name ) { this . acceptKey ( node , name ) ; if ( ! node [ name ] ) { throw new _exception2 [ 'default' ] ( node . type + ' requires ' + name ) ; } }
Performs an accept operation with added sanity check to ensure required keys are not removed.
Performs an accept operation with added sanity check to ensure required keys are not removed .