devdocs/elisp/nonlocal-exits.html


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 <h3 class="section">Nonlocal Exits</h3>  <p>A <em>nonlocal exit</em> is a transfer of control from one point in a program to another remote point. Nonlocal exits can occur in Emacs Lisp as a result of errors; you can also use them under explicit control. Nonlocal exits unbind all variable bindings made by the constructs being exited. </p> <table class="menu" border="0" cellspacing="0"> <tr>
<td align="left" valign="top">• <a href="catch-and-throw" accesskey="1">Catch and Throw</a>
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<td> </td>
<td align="left" valign="top">Nonlocal exits for the program’s own purposes. </td>
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<td align="left" valign="top">• <a href="examples-of-catch" accesskey="2">Examples of Catch</a>
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<td align="left" valign="top">Showing how such nonlocal exits can be written. </td>
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<td align="left" valign="top">• <a href="errors" accesskey="3">Errors</a>
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<td> </td>
<td align="left" valign="top">How errors are signaled and handled. </td>
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<td align="left" valign="top">• <a href="cleanups" accesskey="4">Cleanups</a>
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<td align="left" valign="top">Arranging to run a cleanup form if an error happens. </td>
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    Copyright &copy; 1990-1996, 1998-2022 Free Software Foundation, Inc. <br>Licensed under the GNU GPL license.<br>
    <a href="https://www.gnu.org/software/emacs/manual/html_node/elisp/Nonlocal-Exits.html" class="_attribution-link">https://www.gnu.org/software/emacs/manual/html_node/elisp/Nonlocal-Exits.html</a>
  </p>
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