for ( var i = 0, length = elems.length; i < length; i++ ) {
var value = callback( elems[ i ], i );
- if ( value !== null && value != undefined ) {
- if ( value.constructor != Array )
- value = [ value ];
-
- ret = ret.concat( value );
- }
+ if ( value != null )
+ ret[ ret.length ] = value;
}
- return ret;
+ return ret.concat.apply( [], ret );
}
});