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2.6 KiB
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14 lines
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<?xml version="1.0" encoding="ISO-8859-1" standalone="no"?>
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<html xmlns="http://www.w3.org/1999/xhtml"><head><title>bottom-up implementation</title><link rel="stylesheet" href="../../jargon.css" type="text/css"/><meta name="generator" content="DocBook XSL Stylesheets V1.61.0"/><link rel="home" href="../index.html" title="The Jargon File"/><link rel="up" href="../B.html" title="B"/><link rel="previous" href="bottom-post.html" title="bottom-post"/><link rel="next" href="bounce.html" title="bounce"/></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">bottom-up implementation</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="bottom-post.html">Prev</a><EFBFBD></td><th width="60%" align="center">B</th><td width="20%" align="right"><EFBFBD><a accesskey="n" href="bounce.html">Next</a></td></tr></table><hr/></div><dt><a id="bottom-up-implementation"/><dt xmlns="" id="bottom-up-implementation"><b>bottom-up implementation</b>: <span xmlns="http://www.w3.org/1999/xhtml" class="grammar">n.</span></dt></dt><dd><p> Hackish opposite of the techspeak term <span class="firstterm">top-down design</span>. It has been received wisdom
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in most programming cultures that it is best to design from higher levels
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of abstraction down to lower, specifying sequences of action in increasing
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detail until you get to actual code. Hackers often find (especially in
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exploratory designs that cannot be closely specified in advance) that it
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works best to <span class="emphasis"><em>build</em></span> things in the opposite order, by
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writing and testing a clean set of primitive operations and then knitting
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them together. Naively applied, this leads to hacked-together bottom-up
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implementations; a more sophisticated response is <span class="firstterm">middle-out implementation</span>, in which scratch
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code within primitives at the mid-level of the system is gradually replaced
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with a more polished version of the lowest level at the same time the
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structure above the midlevel is being built. </p></dd><div class="navfooter"><hr/><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="bottom-post.html">Prev</a><EFBFBD></td><td width="20%" align="center"><a accesskey="u" href="../B.html">Up</a></td><td width="40%" align="right"><EFBFBD><a accesskey="n" href="bounce.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">bottom-post<73></td><td width="20%" align="center"><a accesskey="h" href="../index.html">Home</a></td><td width="40%" align="right" valign="top"><EFBFBD>bounce</td></tr></table></div></body></html>
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