UIZE JavaScript Framework

2013 NEWS 2013-03-30 - New Uize.push Method

The new Uize.push static method, implemented in the Uize base module, lets you conveniently push / append the elements from a source list onto the end of a target list.


targetListARRAYorOBJ = Uize.push (targetListARRAYorOBJ,sourceListARRAYorOBJ);

While the elements from a source list object can be appended at the end of a target array with an expression like targetArray.push.apply (targetArray,sourceList), appending the elements from a source list object at the end of a target list object is even a little more cumbersome with ugly expressions like Array.prototype.push.apply (targetList,sourceList) or [].push.apply (targetList,sourceList) (if you're OK with creating an empty array for immediate garbage collection).

Expressions like this are hard to remember when you need to conjure them up, and they're equally unpleasant to make sense of when you see them in your code. The Uize.push method provides a more semantically elegant way to push the elements of a source list onto the end of a target list, allowing both the source and target to be list objects like array instances, arguments objects, or any object with a length property whose value is a number - basically, any value that would produce the result true when passed to the Uize.isList static method.


Uize.push (allOfTheNodes,document.getElementsByTagName ('div'));

In the above example, the elements from the HTMLCollection object returned by the document.getElementById method are being pushed onto the end of the allOfTheNodes array.


  registeredFruits = [],
  fruitRegistered = {}

function registerFruits () {
  Uize.push (registeredFruits,arguments);
  Uize.lookup (arguments,1,fruitRegistered);

registerFruits ('apple','pear','peach');
registerFruits ('banana','orange','mango');

alert (registeredFruits);       // alerts "apple,pear,peach,banana,orange,mango"
alert (fruitRegistered.apple);  // alerts "1"
alert (fruitRegistered.mango);  // alerts "1"

In the above example, the registerFruits variadic function allows any number of fruits to be registered by specifying the names of the fruits using an arbitrarily long arguments list. The function uses the Uize.push method to push the contents of the arguments list object onto the end of the registeredFruits array. It also uses the Uize.lookup method to add entries for the fruits being added to the fruitRegistered lookup object, by specifying the fruitRegistered object as the target for the lookup creation operation.