span class="type-var">'a</span> <a href="../index.html#type-t">t</a></span></span></code></div><div class="spec-doc"><p><code>p &lt;|&gt; q</code> returns a parser encapsulating value <code>a</code> where,</p><ul><li><code>p</code>,<code>q</code> are evaluated sequentially in order as given.</li><li><code>a</code> is the parsed value of <code>p</code> if <code>p</code> is successful</li><li><code>a</code> is the parsed value of <code>q</code> if <code>p</code> is a failure and <code>q</code> is a success.</