Array.prototype.slice appears 5 times in jQueryArray.prototype.push appears 2 times in jQuery

There are several places where the cached value can be reused but are not as well.

These could be cached at the beginning along with window and undefined.

var window = this
    ,undefined
    ,push = Array.prototype.push
    ,slice = Array.prototype.slice

/* ... snip ... */

  if ( toString.call(array) === "[object Array]" ) {
    Array.prototype.push.apply( ret, array );
  }

/* ... snip ... */

  if ( !prune ) {
    push.apply( results, checkSet );
  }

/* ... snip ... */

  if ( !inplace ) {
    result.push.apply( result, ret );
  }

/* ... snip ... */

  slice.call(this);
  push.call(this, ...);

// For internal use only.
// Behaves like an Array's method, not like a jQuery method.
  push: push,

Possibly other uses that I haven't caught. Just a general improvement that could be resued over and over and over.