Simplest code for array intersection in javascript

Use a combination of Array.prototype.filter and Array.prototype.indexOf:

<span class="pln">array1</span><span class="pun">.</span><span class="pln">filter</span><span class="pun">(</span><span class="pln">value </span><span class="pun">=></span> <span class="pun">-</span><span class="lit">1</span> <span class="pun">!==</span><span class="pln"> array2</span><span class="pun">.</span><span class="pln">indexOf</span><span class="pun">(</span><span class="pln">value</span><span class="pun">));</span>

 

Performance Benchmark:

http://jsfiddle.net/321juyLu/2/