slice() end count error

[pjobson]

This is kind of particularity I found when working with negative indexes and slice. I'm not 100% sure if it is a bug or expected behavior.

I'll just get onto the example:

<ul>

<li>0</li> <li>1</li> <li>2</li> <li>3</li> <li>4</li> <li>5</li> <li>6</li> <li>7</li> <li>8</li> <li>9</li> <li>10</li> <li>11</li> <li>12</li> <li>13</li> <li>14</li> <li>15</li> <li>16</li> <li>17</li> <li>18</li> <li>19</li>

</ul> <script type="text/javascript">

var x = [-20,-19,-18,-17,-16,-15,-14,-13,-12,-11,-10,-9,-8,-7,-6,-5,-4,-3,-2,-1,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19];

$.each(x,function(a,b) {

console.log(b,$('li').slice(b,b+1))

});

console.log($('li').slice(-1,0));

console.log($('li').slice(-1));

</script>

When variable b gets to -1, nothing is returned, though I expect what should be returned is the li at the 19th position.

The final two console.log examples show it failing then succeeding, the main concern is if the second variable must be something (not null or ), it makes it kind of a pain in the butt to do dynamic list indexing, as I would have to do some kludge like the following:

var x; if (b==-1) { x = $('li').slice(b); } else { x = $('li').slice(b,b+1); }

[snover]

Thanks for the report, but this is not a jQuery bug. jQuery simply inherits the browser’s native Array.slice functionality. You will need to use a conditional as you suggested at the end of the bug description.  test case

[snover]

 Extended test case