function(){
					if (arguments.length > 0) {
						for (var i=0; i<arguments.length; i++) {
							chain.push(arguments[i]);
						}
						group = chain[chain.length-1];
					}
					else group = false;

					advance_exec_cursor();

					return chainedAPI;
				}
function(){
					if (arguments.length > 0) {
						for (var i=0; i<arguments.length; i++) {
							chain.push(arguments[i]);
						}
						group = chain[chain.length-1];
					}
					else group = false;

					advance_exec_cursor();

					return chainedAPI;
				}
function ( ) { if ( arguments . length > 0 ) { for ( var i = 0 ; i < arguments . length ; i ++ ) { chain . push ( arguments [ i ] ) ; } group = chain [ chain . length - 1 ] ; } else group = false ; advance_exec_cursor ( ) ; return chainedAPI ; }
force LABjs to pause in execution at this point in the chain, until the execution thus far finishes, before proceeding
force LABjs to pause in execution at this point in the chain until the execution thus far finishes before proceeding