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<h1>Module <a href="type_Exception.html">Exception</a></h1>
<pre><span class="keyword">module</span> Exception: <code class="code">sig</code> <a href="Exception.html">..</a> <code class="code">end</code></pre><div class="info">
Exception is a purely functional replacement of
OCaml's built-in exceptions.
<p>
To indicate a normal value use <a href="Exception.html#VALreturn"><code class="code">Exception.return</code></a>. For
exceptional conditions use <a href="Exception.html#VALthrow"><code class="code">Exception.throw</code></a>. Function
<a href="Exception.html#VALcatch"><code class="code">Exception.catch</code></a> splices in an exception handler into the
thread of control. Execute an exception monad with
<a href="Exception.html#VALrun"><code class="code">Exception.run</code></a>.<br>
</div>
<hr width="100%">
<pre><span id="TYPEt"><span class="keyword">type</span> <code class="type">('left, 'right)</code> t</span> </pre>
<div class="info">
Type of an exception monad. <code class="code">'left</code> is the exception's type and
<code class="code">'right</code> is the normal value's type.<br>
</div>
<pre><span id="VALbind"><span class="keyword">val</span> bind</span> : <code class="type">('left, 'right) <a href="Exception.html#TYPEt">t</a> -><br> ('right -> ('left, 'new_right) <a href="Exception.html#TYPEt">t</a>) -><br> ('left, 'new_right) <a href="Exception.html#TYPEt">t</a></code></pre><div class="info">
<code class="code">bind a_monad a_function</code>
<p>
Apply <code class="code">a_function</code> to <code class="code">a_monad</code> producing another monad.
<code class="code">a_function</code> takes a normal value as argument and returns a
monad.<br>
</div>
<pre><span id="VALreturn"><span class="keyword">val</span> return</span> : <code class="type">'right -> ('left, 'right) <a href="Exception.html#TYPEt">t</a></code></pre><div class="info">
<code class="code">return a_normal_value</code>
<p>
Answer <code class="code">a_normal_value</code>.<br>
</div>
<pre><span id="VALthrow"><span class="keyword">val</span> throw</span> : <code class="type">'left -> ('left, 'right) <a href="Exception.html#TYPEt">t</a></code></pre><div class="info">
<code class="code">throw an_exception</code>
<p>
Answer <code class="code">an_exception</code>, or in other words, throw <code class="code">an_exception</code>.<br>
</div>
<pre><span id="VALcatch"><span class="keyword">val</span> catch</span> : <code class="type">('left, 'right) <a href="Exception.html#TYPEt">t</a> -><br> ('left -> ('new_left, 'right) <a href="Exception.html#TYPEt">t</a>) -> ('new_left, 'right) <a href="Exception.html#TYPEt">t</a></code></pre><div class="info">
<code class="code">catch a_monad an_exception_handler</code>
<p>
Catch exceptions from <code class="code">a_monad</code> and feed them into
<code class="code">an_exception_handler</code>. <code class="code">an_exception_handler</code> takes an
exceptional value as argument and returns a monad.<br>
</div>
<pre><span id="VALrun"><span class="keyword">val</span> run</span> : <code class="type">('left -> 'a) -> ('right -> 'a) -> ('left, 'right) <a href="Exception.html#TYPEt">t</a> -> 'a</code></pre><div class="info">
<code class="code">run a_failure_function a_success_function a_monad</code>
<p>
Run <code class="code">a_monad</code>. If <code class="code">a_monad</code> does not <a href="Exception.html#VALthrow"><code class="code">Exception.throw</code></a> an
exception, pass the result of evaluating the monad to
<code class="code">a_success_function</code>. Otherwise, if the <code class="code">a_monad</code> throws, pass
the exception to <code class="code">a_failure_function</code>.<br>
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