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MLton
20241230
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<h1>MLtonExn</h1>
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<pre class="rouge highlight"><code data-lang="sml"><span class="kr">signature</span> <span class="nn">MLTON_EXN</span> <span class="p">=</span>
   <span class="kr">sig</span>
      <span class="kr">val</span> <span class="nv">addExnMessager</span><span class="p">:</span> <span class="p">(</span><span class="n">exn</span> <span class="p">-&gt;</span> <span class="n">string</span> <span class="n">option</span><span class="p">)</span> <span class="p">-&gt;</span> <span class="n">unit</span>
      <span class="kr">val</span> <span class="nv">history</span><span class="p">:</span> <span class="n">exn</span> <span class="p">-&gt;</span> <span class="n">string</span> <span class="n">list</span>

      <span class="kr">val</span> <span class="nv">defaultTopLevelHandler</span><span class="p">:</span> <span class="n">exn</span> <span class="p">-&gt;</span> <span class="nd">'a</span>
      <span class="kr">val</span> <span class="nv">getTopLevelHandler</span><span class="p">:</span> <span class="n">unit</span> <span class="p">-&gt;</span> <span class="p">(</span><span class="n">exn</span> <span class="p">-&gt;</span> <span class="n">unit</span><span class="p">)</span>
      <span class="kr">val</span> <span class="nv">setTopLevelHandler</span><span class="p">:</span> <span class="p">(</span><span class="n">exn</span> <span class="p">-&gt;</span> <span class="n">unit</span><span class="p">)</span> <span class="p">-&gt;</span> <span class="n">unit</span>
      <span class="kr">val</span> <span class="nv">topLevelHandler</span><span class="p">:</span> <span class="n">exn</span> <span class="p">-&gt;</span> <span class="nd">'a</span>
   <span class="kr">end</span></code></pre>
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<ul>
<li>
<p><code>addExnMessager f</code></p>
<div class="paragraph">
<p>adds <code>f</code> as a pretty-printer to be used by <code>General.exnMessage</code> for
converting exceptions to strings.  Messagers are tried in order from
most recently added to least recently added.</p>
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</li>
<li>
<p><code>history e</code></p>
<div class="paragraph">
<p>returns call stack at the point that <code>e</code> was first raised.  Each
element of the list is a file position.  The elements are in reverse
chronological order, i.e. the function called last is at the front of
the list.</p>
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<div class="paragraph">
<p><code>history e</code> will return <code>[]</code> unless the program is compiled with
<code>-const 'Exn.keepHistory true'</code>.</p>
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</li>
<li>
<p><code>defaultTopLevelHandler e</code></p>
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<p>function that behaves as the default top level handler; that is, print
out the unhandled exception message for <code>e</code> and exit.</p>
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</li>
<li>
<p><code>getTopLevelHandler ()</code></p>
<div class="paragraph">
<p>get the top level handler.</p>
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</li>
<li>
<p><code>setTopLevelHandler f</code></p>
<div class="paragraph">
<p>set the top level handler to the function <code>f</code>.  The function <code>f</code>
should not raise an exception or return normally.</p>
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</li>
<li>
<p><code>topLevelHandler e</code></p>
<div class="paragraph">
<p>behaves as if the top level handler received the exception <code>e</code>.</p>
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Last updated Thu Oct 21 15:53:06 2021 -0400 by Matthew Fluet.
<a href="https://github.com/MLton/mlton/commits/master/doc/guide/src/MLtonExn.adoc">Log</a>
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