70 lines
3.2 KiB
HTML
70 lines
3.2 KiB
HTML
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<html lang="en">
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<head>
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<title>Multiple Extension Languages - Debugging with GDB</title>
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<meta name="description" content="Debugging with GDB">
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<link title="Top" rel="start" href="index.html#Top">
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<link rel="up" href="Extending-GDB.html#Extending-GDB" title="Extending GDB">
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<link rel="prev" href="Auto_002dloading-extensions.html#Auto_002dloading-extensions" title="Auto-loading extensions">
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</head>
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<body>
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<div class="node">
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<a name="Multiple-Extension-Languages"></a>
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<p>
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Next: <a rel="next" accesskey="n" href="Aliases.html#Aliases">Aliases</a>,
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Previous: <a rel="previous" accesskey="p" href="Auto_002dloading-extensions.html#Auto_002dloading-extensions">Auto-loading extensions</a>,
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Up: <a rel="up" accesskey="u" href="Extending-GDB.html#Extending-GDB">Extending GDB</a>
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<hr>
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</div>
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<h3 class="section">23.5 Multiple Extension Languages</h3>
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<p>The Guile and Python extension languages do not share any state,
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and generally do not interfere with each other.
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There are some things to be aware of, however.
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<h4 class="subsection">23.5.1 Python comes first</h4>
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<p>Python was <span class="sc">gdb</span>'s first extension language, and to avoid breaking
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existing behaviour Python comes first. This is generally solved by the
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“first one wins” principle. <span class="sc">gdb</span> maintains a list of enabled
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extension languages, and when it makes a call to an extension language,
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(say to pretty-print a value), it tries each in turn until an extension
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language indicates it has performed the request (e.g., has returned the
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pretty-printed form of a value).
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This extends to errors while performing such requests: If an error happens
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while, for example, trying to pretty-print an object then the error is
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reported and any following extension languages are not tried.
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</body></html>
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