 (<a href="Belt_internalMapString.html#TYPEkey">key</a>, 'c) N.t</code></pre>
<pre><span id="VALmerge"><span class="keyword">val</span> merge</span> : <code class="type">(<a href="Belt_internalMapString.html#TYPEkey">key</a>, 'a) N.t -><br>       (<a href="Belt_internalMapString.html#TYPEkey">key</a>, 'b) N.t -><br>       (<a href="Belt_internalMapString.html#TYPEkey">key</a> -> 'a option -> 'b option -> 'c option) -><br>       (<a href="Belt_internalMapString.html#TYPEkey">key</a>, 'c) N.t</code></pre>
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