ss="constructor">Invalid_argument</span></code> if the two lists have
   different lengths.<br>
</div>
<pre><span id="VALmap2"><span class="keyword">val</span> map2</span> : <code class="type">('a -&gt; 'b -&gt; 'c) -&gt; 'a list -&gt; 'b list -&gt; 'c list</code></pre><div class="info">
<code class="code"><span class="constructor">List</span>.map2 f [a1; ...; an] [b1; ...; bn]</code> is
   <code class="code">[f a1 b1; ...; f an bn]</code>.
   Raise <code class="code"><span class="constructor">Invalid_argum