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<h1><a href="../cli/npm-dedupe.html">npm-dedupe</a></h1> <p>Reduce duplication</p>

<h2 id="SYNOPSIS">SYNOPSIS</h2>

<pre><code>npm dedupe [package names...]
npm ddp [package names...]</code></pre>

<h2 id="DESCRIPTION">DESCRIPTION</h2>

<p>Searches the local package tree and attempts to simplify the overall
structure by moving dependencies further up the tree, where they can
be more effectively shared by multiple dependent packages.</p>

<p>For example, consider this dependency graph:</p>

<pre><code>a
+-- b &lt;-- depends on c@1.0.x
|   `-- c@1.0.3
`-- d &lt;-- depends on c@~1.0.9
    `-- c@1.0.10</code></pre>

<p>In this case, <code><a href="../cli/npm-dedupe.html">npm-dedupe(1)</a></code> will transform the tree to:</p>

<pre><code>a
+-- b
+-- d
`-- c@1.0.10</code></pre>

<p>Because of the hierarchical nature of node&#39;s module lookup, b and d
will both get their dependency met by the single c package at the root
level of the tree.</p>

<p>If a suitable version exists at the target location in the tree
already, then it will be left untouched, but the other duplicates will
be deleted.</p>

<p>If no suitable version can be found, then a warning is printed, and
nothing is done.</p>

<p>If any arguments are supplied, then they are filters, and only the
named packages will be touched.</p>

<p>Note that this operation transforms the dependency tree, and may
result in packages getting updated versions, perhaps from the npm
registry.</p>

<p>This feature is experimental, and may change in future versions.</p>

<p>The <code>--tag</code> argument will apply to all of the affected dependencies. If a
tag with the given name exists, the tagged version is preferred over newer
versions.</p>

<h2 id="SEE-ALSO">SEE ALSO</h2>

<ul><li><a href="../cli/npm-ls.html">npm-ls(1)</a></li><li><a href="../cli/npm-update.html">npm-update(1)</a></li><li><a href="../cli/npm-install.html">npm-install(1)</a></li></ul>
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<p id="footer">npm-dedupe &mdash; npm@1.3.21</p>
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