pan class="type-var">'input</span>, <span class="type-var">'output</span>, <span class="type-var">'error</span>, <span class="type-var">'security</span>)</span> <a href="index.html#type-post_service0">post_service0</a></span> <span>&#45;&gt;</span> <span><span><span>(<span class="type-var">'output</span>, <span class="type-var">'error</span>)</span> <a href="index.html#type-api_result">api_result</a></span> Lwt.t</span></code></dt><dt class="spec value" id="val-post1"><a href="#val-post1" class="anchor"