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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, |
| and generally do not interfere with each other. |
| 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 |
| existing behaviour Python comes first. This is generally solved by the |
| “first one wins” principle. <span class="sc">gdb</span> maintains a list of enabled |
| extension languages, and when it makes a call to an extension language, |
| (say to pretty-print a value), it tries each in turn until an extension |
| language indicates it has performed the request (e.g., has returned the |
| pretty-printed form of a value). |
| This extends to errors while performing such requests: If an error happens |
| while, for example, trying to pretty-print an object then the error is |
| reported and any following extension languages are not tried. |
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