naive javascript quicksort

qsort.js

// naive quicksort

function qsort(a) {

    var len = a.length;

    if ( !len || len === 1 )
        return a;

    var pivot = a[0],
        left  = [],
        right = [];

    for ( var i = 1; i < len; i++ )
        ( a[i] < pivot ? left : right ).push( a[i] );

    return qsort( left ).concat( pivot, qsort(right) );

}