2018-10-02 14:07:06 -04:00
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<section xmlns="http://docbook.org/ns/docbook"
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xmlns:xlink="http://www.w3.org/1999/xlink"
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xmlns:xi="http://www.w3.org/2001/XInclude"
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xml:id="sec-debug">
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2018-10-02 15:59:59 -04:00
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<title>Debugging Nix Expressions</title>
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2018-10-02 14:07:06 -04:00
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2018-10-02 15:59:59 -04:00
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<para>
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Nix is a unityped, dynamic language, this means every value can potentially
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appear anywhere. Since it is also non-strict, evaluation order and what
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ultimately is evaluated might surprise you. Therefore it is important to be
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able to debug nix expressions.
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</para>
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2018-10-02 14:07:06 -04:00
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2018-10-02 15:59:59 -04:00
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<para>
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In the <literal>lib/debug.nix</literal> file you will find a number of
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functions that help (pretty-)printing values while evaluation is runnnig. You
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can even specify how deep these values should be printed recursively, and
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transform them on the fly. Please consult the docstrings in
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<literal>lib/debug.nix</literal> for usage information.
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</para>
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</section>
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