.\" generated with Ronn/v0.7.3
.\" http://github.com/rtomayko/ronn/tree/0.7.3
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.TH "NPM\-DEDUPE" "1" "August 2014" "" ""
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.SH "NAME"
\fBnpm\-dedupe\fR \- Reduce duplication
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.SH "SYNOPSIS"
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.nf

npm dedupe [package names\.\.\.]
npm ddp [package names\.\.\.]
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.fi
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.SH "DESCRIPTION"
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\.
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.P
For example, consider this dependency graph:
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.IP "" 4
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.nf

a
+\-\- b <\-\- depends on c@1\.0\.x
|   `\-\- c@1\.0\.3
`\-\- d <\-\- depends on c@~1\.0\.9
    `\-\- c@1\.0\.10
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.fi
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.IP "" 0
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.P
npm help In this case, \fBnpm\-dedupe\fR will transform the tree to:
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.IP "" 4
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.nf

a
+\-\- b
+\-\- d
`\-\- c@1\.0\.10
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.fi
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.IP "" 0
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.P
Because of the hierarchical nature of node\'s module lookup, b and d will both get their dependency met by the single c package at the root level of the tree\.
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.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\.
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.P
If no suitable version can be found, then a warning is printed, and nothing is done\.
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.P
If any arguments are supplied, then they are filters, and only the named packages will be touched\.
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.P
Note that this operation transforms the dependency tree, and may result in packages getting updated versions, perhaps from the npm registry\.
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.P
This feature is experimental, and may change in future versions\.
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.P
The \fB\-\-tag\fR 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\.
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.SH "SEE ALSO"
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.IP "\(bu" 4
npm help ls
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.IP "\(bu" 4
npm help update
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.IP "\(bu" 4
npm help install
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.IP "" 0