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*NERD_tree.txt*   A tree explorer plugin that owns your momma!



    omg its ... ~

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    / / / /_/ / __/    /  |/ / __/ / /_/ / / / /    / / / /_/ / __/ / __/   ~
   / / / __  / /___   / /|  / /___/ _, _/ /_/ /    / / / _, _/ /___/ /___   ~
  /_/ /_/ /_/_____/  /_/ |_/_____/_/ |_/_____/    /_/ /_/ |_/_____/_____/   ~


                              Reference Manual~




==============================================================================
CONTENTS                                                   *NERDTree-contents*

    1.Intro...................................|NERDTree|
    2.Functionality provided..................|NERDTreeFunctionality|
        2.1.Global commands...................|NERDTreeGlobalCommands|
        2.2.Bookmarks.........................|NERDTreeBookmarks|
            2.2.1.The bookmark table..........|NERDTreeBookmarkTable|
            2.2.2.Bookmark commands...........|NERDTreeBookmarkCommands|
            2.2.3.Invalid bookmarks...........|NERDTreeInvalidBookmarks|
        2.3.NERD tree mappings................|NERDTreeMappings|
        2.4.The NERD tree menu................|NERDTreeMenu|
    3.Options.................................|NERDTreeOptions|
        3.1.Option summary....................|NERDTreeOptionSummary|
        3.2.Option details....................|NERDTreeOptionDetails|
    4.The NERD tree API.......................|NERDTreeAPI|
        4.1.Key map API.......................|NERDTreeKeymapAPI|
        4.2.Menu API..........................|NERDTreeMenuAPI|
    5.About...................................|NERDTreeAbout|
    6.Changelog...............................|NERDTreeChangelog|
    7.Credits.................................|NERDTreeCredits|
    8.License.................................|NERDTreeLicense|

==============================================================================
1. Intro                                                            *NERDTree*

What is this "NERD tree"??

The NERD tree allows you to explore your filesystem and to open files and
directories. It presents the filesystem to you in the form of a tree which you
manipulate with the keyboard and/or mouse. It also allows you to perform
simple filesystem operations.

The following features and functionality are provided by the NERD tree:
    * Files and directories are displayed in a hierarchical tree structure
    * Different highlighting is provided for the following types of nodes:
        * files
        * directories
        * sym-links
        * windows .lnk files
        * read-only files
        * executable files
    * Many (customisable) mappings are provided to manipulate the tree:
        * Mappings to open/close/explore directory nodes
        * Mappings to open files in new/existing windows/tabs
        * Mappings to change the current root of the tree
        * Mappings to navigate around the tree
        * ...
    * Directories and files can be bookmarked.
    * Most NERD tree navigation can also be done with the mouse
    * Filtering of tree content (can be toggled at runtime)
        * custom file filters to prevent e.g. vim backup files being displayed
        * optional displaying of hidden files (. files)
        * files can be "turned off" so that only directories are displayed
    * The position and size of the NERD tree window can be customised
    * The order in which the nodes in the tree are listed can be customised.
    * A model of your filesystem is created/maintained as you explore it. This
      has several advantages:
        * All filesystem information is cached and is only re-read on demand
        * If you revisit a part of the tree that you left earlier in your
          session, the directory nodes will be opened/closed as you left them
    * The script remembers the cursor position and window position in the NERD
      tree so you can toggle it off (or just close the tree window) and then
      reopen it (with NERDTreeToggle) the NERD tree window will appear exactly
      as you left it
    * You can have a separate NERD tree for each tab, share trees across tabs,
      or a mix of both.
    * By default the script overrides the default file browser (netw), so if
      you :edit a directory a (slighly modified) NERD tree will appear in the
      current window
    * A programmable menu system is provided (simulates right clicking on a
      node)
        * one default menu plugin is provided to perform basic filesytem
          operations (create/delete/move/copy files/directories)
    * There's an API for adding your own keymappings


==============================================================================
2. Functionality provided                              *NERDTreeFunctionality*

------------------------------------------------------------------------------
2.1. Global Commands                                  *NERDTreeGlobalCommands*

:NERDTree [<start-directory> | <bookmark>]                         *:NERDTree*
    Opens a fresh NERD tree. The root of the tree depends on the argument
    given. There are 3 cases: If no argument is given, the current directory
    will be used.  If a directory is given, that will be used. If a bookmark
    name is given, the corresponding directory will be used.  For example: >
        :NERDTree /home/marty/vim7/src
        :NERDTree foo   (foo is the name of a bookmark)
<
:NERDTreeFromBookmark <bookmark>                       *:NERDTreeFromBookmark*
    Opens a fresh NERD tree with the root initialized to the dir for
    <bookmark>.  This only reason to use this command over :NERDTree is for
    the completion (which is for bookmarks rather than directories).

:NERDTreeToggle [<start-directory> | <bookmark>]             *:NERDTreeToggle*
    If a NERD tree already exists for this tab, it is reopened and rendered
    again.  If no NERD tree exists for this tab then this command acts the
    same as the |:NERDTree| command.

:NERDTreeMirror                                              *:NERDTreeMirror*
    Shares an existing NERD tree, from another tab, in the current tab.
    Changes made to one tree are reflected in both as they are actually the
    same buffer.

    If only one other NERD tree exists, that tree is automatically mirrored. If
    more than one exists, the script will ask which tree to mirror.

:NERDTreeClose                                                *:NERDTreeClose*
    Close the NERD tree in this tab.

:NERDTreeFind                                                  *:NERDTreeFind*
    Find the current file in the tree. If no tree exists for the current tab,
    or the file is not under the current root, then initialize a new tree where
    the root is the directory of the current file.

------------------------------------------------------------------------------
2.2. Bookmarks                                             *NERDTreeBookmarks*

Bookmarks in the NERD tree are a way to tag files or directories of interest.
For example, you could use bookmarks to tag all of your project directories.

------------------------------------------------------------------------------
2.2.1. The Bookmark Table                              *NERDTreeBookmarkTable*

If the bookmark table is active (see |NERDTree-B| and
|'NERDTreeShowBookmarks'|), it will be rendered above the tree. You can double
click bookmarks or use the |NERDTree-o| mapping to activate them. See also,
|NERDTree-t| and |NERDTree-T|

------------------------------------------------------------------------------
2.2.2. Bookmark commands                            *NERDTreeBookmarkCommands*

Note that the following commands are only available in the NERD tree buffer.

:Bookmark <name>
    Bookmark the current node as <name>. If there is already a <name>
    bookmark, it is overwritten. <name> must not contain spaces.

:BookmarkToRoot <bookmark>
    Make the directory corresponding to <bookmark> the new root. If a treenode
    corresponding to <bookmark> is already cached somewhere in the tree then
    the current tree will be used, otherwise a fresh tree will be opened.
    Note that if <bookmark> points to a file then its parent will be used
    instead.

:RevealBookmark <bookmark>
    If the node is cached under the current root then it will be revealed
    (i.e. directory nodes above it will be opened) and the cursor will be
    placed on it.

:OpenBookmark <bookmark>
    <bookmark> must point to a file. The file is opened as though |NERDTree-o|
    was applied. If the node is cached under the current root then it will be
    revealed and the cursor will be placed on it.

:ClearBookmarks [<bookmarks>]
    Remove all the given bookmarks. If no bookmarks are given then remove all
    bookmarks on the current node.

:ClearAllBookmarks
    Remove all bookmarks.

:ReadBookmarks
    Re-read the bookmarks in the |'NERDTreeBookmarksFile'|.

See also |:NERDTree| and |:NERDTreeFromBookmark|.

------------------------------------------------------------------------------
2.2.3. Invalid Bookmarks                            *NERDTreeInvalidBookmarks*

If invalid bookmarks are detected, the script will issue an error message and
the invalid bookmarks will become unavailable for use.

These bookmarks will still be stored in the bookmarks file (see
|'NERDTreeBookmarksFile'|), down the bottom. There will always be a blank line
after the valid bookmarks but before the invalid ones.

Each line in the bookmarks file represents one bookmark. The proper format is:
<bookmark name><space><full path to the bookmark location>

After you have corrected any invalid bookmarks, either restart vim, or go
:ReadBookmarks from the NERD tree window.

------------------------------------------------------------------------------
2.3. NERD tree Mappings                                     *NERDTreeMappings*

Default  Description~                                             help-tag~
Key~

o.......Open files, directories and bookmarks....................|NERDTree-o|
go......Open selected file, but leave cursor in the NERDTree.....|NERDTree-go|
t.......Open selected node/bookmark in a new tab.................|NERDTree-t|
T.......Same as 't' but keep the focus on the current tab........|NERDTree-T|
i.......Open selected file in a split window.....................|NERDTree-i|
gi......Same as i, but leave the cursor on the NERDTree..........|NERDTree-gi|
s.......Open selected file in a new vsplit.......................|NERDTree-s|
gs......Same as s, but leave the cursor on the NERDTree..........|NERDTree-gs|
O.......Recursively open the selected directory..................|NERDTree-O|
x.......Close the current nodes parent...........................|NERDTree-x|
X.......Recursively close all children of the current node.......|NERDTree-X|
e.......Edit the current dif.....................................|NERDTree-e|

<CR>...............same as |NERDTree-o|.
double-click.......same as the |NERDTree-o| map.
middle-click.......same as |NERDTree-i| for files, same as
                   |NERDTree-e| for dirs.

D.......Delete the current bookmark .............................|NERDTree-D|

P.......Jump to the root node....................................|NERDTree-P|
p.......Jump to current nodes parent.............................|NERDTree-p|
K.......Jump up inside directories at the current tree depth.....|NERDTree-K|
J.......Jump down inside directories at the current tree depth...|NERDTree-J|
<C-J>...Jump down to the next sibling of the current directory...|NERDTree-C-J|
<C-K>...Jump up to the previous sibling of the current directory.|NERDTree-C-K|

C.......Change the tree root to the selected dir.................|NERDTree-C|
u.......Move the tree root up one directory......................|NERDTree-u|
U.......Same as 'u' except the old root node is left open........|NERDTree-U|
r.......Recursively refresh the current directory................|NERDTree-r|
R.......Recursively refresh the current root.....................|NERDTree-R|
m.......Display the NERD tree menu...............................|NERDTree-m|
cd......Change the CWD to the dir of the selected node...........|NERDTree-cd|

I.......Toggle whether hidden files displayed....................|NERDTree-I|
f.......Toggle whether the file filters are used.................|NERDTree-f|
F.......Toggle whether files are displayed.......................|NERDTree-F|
B.......Toggle whether the bookmark table is displayed...........|NERDTree-B|

q.......Close the NERDTree window................................|NERDTree-q|
A.......Zoom (maximize/minimize) the NERDTree window.............|NERDTree-A|
?.......Toggle the display of the quick help.....................|NERDTree-?|

------------------------------------------------------------------------------
                                                                  *NERDTree-o*
Default key: o
Map option: NERDTreeMapActivateNode
Applies to: files and directories.

If a file node is selected, it is opened in the previous window.

If a directory is selected it is opened or closed depending on its current
state.

If a bookmark that links to a directory is selected then that directory
becomes the new root.

If a bookmark that links to a file is selected then that file is opened in the
previous window.

------------------------------------------------------------------------------
                                                                 *NERDTree-go*
Default key: go
Map option: None
Applies to: files.

If a file node is selected, it is opened in the previous window, but the
cursor does not move.

The key combo for this mapping is always "g" + NERDTreeMapActivateNode (see
|NERDTree-o|).

------------------------------------------------------------------------------
                                                                  *NERDTree-t*
Default key: t
Map option: NERDTreeMapOpenInTab
Applies to: files and directories.

Opens the selected file in a new tab. If a directory is selected, a fresh
NERD Tree for that directory is opened in a new tab.

If a bookmark which points to a directory is selected, open a NERD tree for
that directory in a new tab. If the bookmark points to a file, open that file
in a new tab.

------------------------------------------------------------------------------
                                                                  *NERDTree-T*
Default key: T
Map option: NERDTreeMapOpenInTabSilent
Applies to: files and directories.

The same as |NERDTree-t| except that the focus is kept in the current tab.

------------------------------------------------------------------------------
                                                                  *NERDTree-i*
Default key: i
Map option: NERDTreeMapOpenSplit
Applies to: files.

Opens the selected file in a new split window and puts the cursor in the new
window.

------------------------------------------------------------------------------
                                                                 *NERDTree-gi*
Default key: gi
Map option: None
Applies to: files.

The same as |NERDTree-i| except that the cursor is not moved.

The key combo for this mapping is always "g" + NERDTreeMapOpenSplit (see
|NERDTree-i|).

------------------------------------------------------------------------------
                                                                  *NERDTree-s*
Default key: s
Map option: NERDTreeMapOpenVSplit
Applies to: files.

Opens the selected file in a new vertically split window and puts the cursor in
the new window.

------------------------------------------------------------------------------
                                                                 *NERDTree-gs*
Default key: gs
Map option: None
Applies to: files.

The same as |NERDTree-s| except that the cursor is not moved.

The key combo for this mapping is always "g" + NERDTreeMapOpenVSplit (see
|NERDTree-s|).

------------------------------------------------------------------------------
                                                                  *NERDTree-O*
Default key: O
Map option: NERDTreeMapOpenRecursively
Applies to: directories.

Recursively opens the selelected directory.

All files and directories are cached, but if a directory would not be
displayed due to file filters (see |'NERDTreeIgnore'| |NERDTree-f|) or the
hidden file filter (see |'NERDTreeShowHidden'|) then its contents are not
cached. This is handy, especially if you have .svn directories.

------------------------------------------------------------------------------
                                                                  *NERDTree-x*
Default key: x
Map option: NERDTreeMapCloseDir
Applies to: files and directories.

Closes the parent of the selected node.

------------------------------------------------------------------------------
                                                                  *NERDTree-X*
Default key: X
Map option: NERDTreeMapCloseChildren
Applies to: directories.

Recursively closes all children of the selected directory.

Tip: To quickly "reset" the tree, use |NERDTree-P| with this mapping.

------------------------------------------------------------------------------
                                                                  *NERDTree-e*
Default key: e
Map option: NERDTreeMapOpenExpl
Applies to: files and directories.

|:edit|s the selected directory, or the selected file's directory. This could
result in a NERD tree or a netrw being opened, depending on
|'NERDTreeHijackNetrw'|.

------------------------------------------------------------------------------
                                                                  *NERDTree-D*
Default key: D
Map option: NERDTreeMapDeleteBookmark
Applies to: lines in the bookmarks table

Deletes the currently selected bookmark.

------------------------------------------------------------------------------
                                                                  *NERDTree-P*
Default key: P
Map option: NERDTreeMapJumpRoot
Applies to: no restrictions.

Jump to the tree root.

------------------------------------------------------------------------------
                                                                  *NERDTree-p*
Default key: p
Map option: NERDTreeMapJumpParent
Applies to: files and directories.

Jump to the parent node of the selected node.

------------------------------------------------------------------------------
                                                                  *NERDTree-K*
Default key: K
Map option: NERDTreeMapJumpFirstChild
Applies to: files and directories.

Jump to the first child of the current nodes parent.

If the cursor is already on the first node then do the following:
    * loop back thru the siblings of the current nodes parent until we find an
      open dir with children
    * go to the first child of that node

------------------------------------------------------------------------------
                                                                  *NERDTree-J*
Default key: J
Map option: NERDTreeMapJumpLastChild
Applies to: files and directories.

Jump to the last child of the current nodes parent.

If the cursor is already on the last node then do the following:
    * loop forward thru the siblings of the current nodes parent until we find
      an open dir with children
    * go to the last child of that node

------------------------------------------------------------------------------
                                                                *NERDTree-C-J*
Default key: <C-J>
Map option: NERDTreeMapJumpNextSibling
Applies to: files and directories.

Jump to the next sibling of the selected node.

------------------------------------------------------------------------------
                                                                *NERDTree-C-K*
Default key: <C-K>
Map option: NERDTreeMapJumpPrevSibling
Applies to: files and directories.

Jump to the previous sibling of the selected node.

------------------------------------------------------------------------------
                                                                  *NERDTree-C*
Default key: C
Map option: NERDTreeMapChdir
Applies to: directories.

Make the selected directory node the new tree root. If a file is selected, its
parent is used.

------------------------------------------------------------------------------
                                                                  *NERDTree-u*
Default key: u
Map option: NERDTreeMapUpdir
Applies to: no restrictions.

Move the tree root up a dir (like doing a "cd ..").

------------------------------------------------------------------------------
                                                                  *NERDTree-U*
Default key: U
Map option: NERDTreeMapUpdirKeepOpen
Applies to: no restrictions.

Like |NERDTree-u| except that the old tree root is kept open.

------------------------------------------------------------------------------
                                                                  *NERDTree-r*
Default key: r
Map option: NERDTreeMapRefresh
Applies to: files and directories.

If a dir is selected, recursively refresh that dir, i.e. scan the filesystem
for changes and represent them in the tree.

If a file node is selected then the above is done on it's parent.

------------------------------------------------------------------------------
                                                                  *NERDTree-R*
Default key: R
Map option: NERDTreeMapRefreshRoot
Applies to: no restrictions.

Recursively refresh the tree root.

------------------------------------------------------------------------------
                                                                  *NERDTree-m*
Default key: m
Map option: NERDTreeMapMenu
Applies to: files and directories.

Display the NERD tree menu. See |NERDTreeMenu| for details.

------------------------------------------------------------------------------
                                                                 *NERDTree-cd*
Default key: cd
Map option: NERDTreeMapChdir
Applies to: files and directories.

Change vims current working directory to that of the selected node.

------------------------------------------------------------------------------
                                                                  *NERDTree-I*
Default key: I
Map option: NERDTreeMapToggleHidden
Applies to: no restrictions.

Toggles whether hidden files (i.e. "dot files") are displayed.

------------------------------------------------------------------------------
                                                                  *NERDTree-f*
Default key: f
Map option: NERDTreeMapToggleFilters
Applies to: no restrictions.

Toggles whether file filters are used. See |'NERDTreeIgnore'| for details.

------------------------------------------------------------------------------
                                                                  *NERDTree-F*
Default key: F
Map option: NERDTreeMapToggleFiles
Applies to: no restrictions.

Toggles whether file nodes are displayed.

------------------------------------------------------------------------------
                                                                  *NERDTree-B*
Default key: B
Map option: NERDTreeMapToggleBookmarks
Applies to: no restrictions.

Toggles whether the bookmarks table is displayed.

------------------------------------------------------------------------------
                                                                  *NERDTree-q*
Default key: q
Map option: NERDTreeMapQuit
Applies to: no restrictions.

Closes the NERDtree window.

------------------------------------------------------------------------------
                                                                  *NERDTree-A*
Default key: A
Map option: NERDTreeMapToggleZoom
Applies to: no restrictions.

Maximize (zoom) and minimize the NERDtree window.

------------------------------------------------------------------------------
                                                                  *NERDTree-?*
Default key: ?
Map option: NERDTreeMapHelp
Applies to: no restrictions.

Toggles whether the quickhelp is displayed.

------------------------------------------------------------------------------
2.3. The NERD tree menu                                         *NERDTreeMenu*

The NERD tree has a menu that can be programmed via the an API (see
|NERDTreeMenuAPI|). The idea is to simulate the "right click" menus that most
file explorers have.

The script comes with two default menu plugins: exec_menuitem.vim and
fs_menu.vim. fs_menu.vim adds some basic filesystem operations to the menu for
creating/deleting/moving/copying files and dirs. exec_menuitem.vim provides a
menu item to execute executable files.

Related tags: |NERDTree-m| |NERDTreeApi|

==============================================================================
3. Customisation                                             *NERDTreeOptions*


------------------------------------------------------------------------------
3.1. Customisation summary                             *NERDTreeOptionSummary*

The script provides the following options that can customise the behaviour the
NERD tree. These options should be set in your vimrc.

|'loaded_nerd_tree'|            Turns off the script.

|'NERDChristmasTree'|           Tells the NERD tree to make itself colourful
                                and pretty.

|'NERDTreeAutoCenter'|          Controls whether the NERD tree window centers
                                when the cursor moves within a specified
                                distance to the top/bottom of the window.
|'NERDTreeAutoCenterThreshold'| Controls the sensitivity of autocentering.

|'NERDTreeCaseSensitiveSort'|   Tells the NERD tree whether to be case
                                sensitive or not when sorting nodes.

|'NERDTreeChDirMode'|           Tells the NERD tree if/when it should change
                                vim's current working directory.

|'NERDTreeHighlightCursorline'| Tell the NERD tree whether to highlight the
                                current cursor line.

|'NERDTreeHijackNetrw'|         Tell the NERD tree whether to replace the netrw
                                autocommands for exploring local directories.

|'NERDTreeIgnore'|              Tells the NERD tree which files to ignore.

|'NERDTreeBookmarksFile'|       Where the bookmarks are stored.

|'NERDTreeMouseMode'|           Tells the NERD tree how to handle mouse
                                clicks.

|'NERDTreeQuitOnOpen'|          Closes the tree window after opening a file.

|'NERDTreeShowBookmarks'|       Tells the NERD tree whether to display the
                                bookmarks table on startup.

|'NERDTreeShowFiles'|           Tells the NERD tree whether to display files
                                in the tree on startup.

|'NERDTreeShowHidden'|          Tells the NERD tree whether to display hidden
                                files on startup.

|'NERDTreeShowLineNumbers'|     Tells the NERD tree whether to display line
                                numbers in the tree window.

|'NERDTreeSortOrder'|           Tell the NERD tree how to sort the nodes in
                                the tree.

|'NERDTreeStatusline'|          Set a statusline for NERD tree windows.

|'NERDTreeWinPos'|              Tells the script where to put the NERD tree
                                window.

|'NERDTreeWinSize'|             Sets the window size when the NERD tree is
                                opened.

------------------------------------------------------------------------------
3.2. Customisation details                             *NERDTreeOptionDetails*

To enable any of the below options you should put the given line in your
~/.vimrc

                                                          *'loaded_nerd_tree'*
If this plugin is making you feel homicidal, it may be a good idea to turn it
off with this line in your vimrc: >
    let loaded_nerd_tree=1
<
------------------------------------------------------------------------------
                                                         *'NERDChristmasTree'*
Values: 0 or 1.
Default: 1.

If this option is set to 1 then some extra syntax highlighting elements are
added to the nerd tree to make it more colourful.

Set it to 0 for a more vanilla looking tree.

------------------------------------------------------------------------------
                                                        *'NERDTreeAutoCenter'*
Values: 0 or 1.
Default: 1

If set to 1, the NERD tree window will center around the cursor if it moves to
within |'NERDTreeAutoCenterThreshold'| lines of the top/bottom of the window.

This is ONLY done in response to tree navigation mappings,
i.e. |NERDTree-J| |NERDTree-K| |NERDTree-C-J| |NERDTree-C-K| |NERDTree-p|
|NERDTree-P|

The centering is done with a |zz| operation.

------------------------------------------------------------------------------
                                               *'NERDTreeAutoCenterThreshold'*
Values: Any natural number.
Default: 3

This option controls the "sensitivity" of the NERD tree auto centering. See
|'NERDTreeAutoCenter'| for details.

------------------------------------------------------------------------------
                                                 *'NERDTreeCaseSensitiveSort'*
Values: 0 or 1.
Default: 0.

By default the NERD tree does not sort nodes case sensitively, i.e. nodes
could appear like this: >
    bar.c
    Baz.c
    blarg.c
    boner.c
    Foo.c
<
But, if you set this option to 1 then the case of the nodes will be taken into
account. The above nodes would then be sorted like this: >
    Baz.c
    Foo.c
    bar.c
    blarg.c
    boner.c
<
------------------------------------------------------------------------------
                                                         *'NERDTreeChDirMode'*

Values: 0, 1 or 2.
Default: 0.

Use this option to tell the script when (if at all) to change the current
working directory (CWD) for vim.

If it is set to 0 then the CWD is never changed by the NERD tree.

If set to 1 then the CWD is changed when the NERD tree is first loaded to the
directory it is initialized in. For example, if you start the NERD tree with >
    :NERDTree /home/marty/foobar
<
then the CWD will be changed to /home/marty/foobar and will not be changed
again unless you init another NERD tree with a similar command.

If the option is set to 2 then it behaves the same as if set to 1 except that
the CWD is changed whenever the tree root is changed. For example, if the CWD
is /home/marty/foobar and you make the node for /home/marty/foobar/baz the new
root then the CWD will become /home/marty/foobar/baz.

------------------------------------------------------------------------------
                                               *'NERDTreeHighlightCursorline'*
Values: 0 or 1.
Default: 1.

If set to 1, the current cursor line in the NERD tree buffer will be
highlighted. This is done using the |'cursorline'| option.

------------------------------------------------------------------------------
                                                       *'NERDTreeHijackNetrw'*
Values: 0 or 1.
Default: 1.

If set to 1, doing a >
    :edit <some directory>
<
will open up a "secondary" NERD tree instead of a netrw in the target window.

Secondary NERD trees behaves slighly different from a regular trees in the
following respects:
    1. 'o' will open the selected file in the same window as the tree,
       replacing it.
    2. you can have as many secondary tree as you want in the same tab.

------------------------------------------------------------------------------
                                                            *'NERDTreeIgnore'*
Values: a list of regular expressions.
Default: ['\~$'].

This option is used to specify which files the NERD tree should ignore.  It
must be a list of regular expressions. When the NERD tree is rendered, any
files/dirs that match any of the regex's in 'NERDTreeIgnore' wont be
displayed.

For example if you put the following line in your vimrc: >
    let NERDTreeIgnore=['\.vim$', '\~$']
<
then all files ending in .vim or ~ will be ignored.

Note: to tell the NERD tree not to ignore any files you must use the following
line: >
    let NERDTreeIgnore=[]
<

The file filters can be turned on and off dynamically with the |NERDTree-f|
mapping.

------------------------------------------------------------------------------
                                                     *'NERDTreeBookmarksFile'*
Values: a path
Default: $HOME/.NERDTreeBookmarks

This is where bookmarks are saved. See |NERDTreeBookmarkCommands|.

------------------------------------------------------------------------------
                                                       *'NERDTreeMouseMode'*
Values: 1, 2 or 3.
Default: 1.

If set to 1 then a double click on a node is required to open it.
If set to 2 then a single click will open directory nodes, while a double
click will still be required for file nodes.
If set to 3 then a single click will open any node.

Note: a double click anywhere on a line that a tree node is on will
activate it, but all single-click activations must be done on name of the node
itself. For example, if you have the following node: >
    | | |-application.rb
<
then (to single click activate it) you must click somewhere in
'application.rb'.

------------------------------------------------------------------------------
                                                        *'NERDTreeQuitOnOpen'*

Values: 0 or 1.
Default: 0

If set to 1, the NERD tree window will close after opening a file with the
|NERDTree-o|, |NERDTree-i|, |NERDTree-t| and |NERDTree-T| mappings.

------------------------------------------------------------------------------
                                                     *'NERDTreeShowBookmarks'*
Values: 0 or 1.
Default: 0.

If this option is set to 1 then the bookmarks table will be displayed.

This option can be toggled dynamically, per tree, with the |NERDTree-B|
mapping.

------------------------------------------------------------------------------
                                                         *'NERDTreeShowFiles'*
Values: 0 or 1.
Default: 1.

If this option is set to 1 then files are displayed in the NERD tree. If it is
set to 0 then only directories are displayed.

This option can be toggled dynamically, per tree, with the |NERDTree-F|
mapping and is useful for drastically shrinking the tree when you are
navigating to a different part of the tree.

------------------------------------------------------------------------------
                                                        *'NERDTreeShowHidden'*
Values: 0 or 1.
Default: 0.

This option tells vim whether to display hidden files by default. This option
can be dynamically toggled, per tree, with the |NERDTree-I| mapping.  Use one
of the follow lines to set this option: >
    let NERDTreeShowHidden=0
    let NERDTreeShowHidden=1
<

------------------------------------------------------------------------------
                                                   *'NERDTreeShowLineNumbers'*
Values: 0 or 1.
Default: 0.

This option tells vim whether to display line numbers for the NERD tree
window.  Use one of the follow lines to set this option: >
    let NERDTreeShowLineNumbers=0
    let NERDTreeShowLineNumbers=1
<

------------------------------------------------------------------------------
                                                         *'NERDTreeSortOrder'*
Values: a list of regular expressions.
Default: ['\/$', '*', '\.swp$',  '\.bak$', '\~$']

This option is set to a list of regular expressions which are used to
specify the order of nodes under their parent.

For example, if the option is set to: >
    ['\.vim$', '\.c$', '\.h$', '*', 'foobar']
<
then all .vim files will be placed at the top, followed by all .c files then
all .h files. All files containing the string 'foobar' will be placed at the
end.  The star is a special flag: it tells the script that every node that
doesnt match any of the other regexps should be placed here.

If no star is present in 'NERDTreeSortOrder' then one is automatically
appended to the array.

The regex '\/$' should be used to match directory nodes.

After this sorting is done, the files in each group are sorted alphabetically.

Other examples: >
    (1) ['*', '\/$']
    (2) []
    (3) ['\/$', '\.rb$', '\.php$', '*', '\.swp$',  '\.bak$', '\~$']
<
1. Directories will appear last, everything else will appear above.
2. Everything will simply appear in alphabetical order.
3. Dirs will appear first, then ruby and php. Swap files, bak files and vim
   backup files will appear last with everything else preceding them.

------------------------------------------------------------------------------
                                                        *'NERDTreeStatusline'*
Values: Any valid statusline setting.
Default: %{b:NERDTreeRoot.path.strForOS(0)}

Tells the script what to use as the |'statusline'| setting for NERD tree
windows.

Note that the statusline is set using |:let-&| not |:set| so escaping spaces
isn't necessary.

Setting this option to -1 will will deactivate it so that your global
statusline setting is used instead.

------------------------------------------------------------------------------
                                                            *'NERDTreeWinPos'*
Values: "left" or "right"
Default: "left".

This option is used to determine where NERD tree window is placed on the
screen.

This option makes it possible to use two different explorer plugins
simultaneously. For example, you could have the taglist plugin on the left of
the window and the NERD tree on the right.

------------------------------------------------------------------------------
                                                           *'NERDTreeWinSize'*
Values: a positive integer.
Default: 31.

This option is used to change the size of the NERD tree when it is loaded.

==============================================================================
4. The NERD tree API                                             *NERDTreeAPI*

The NERD tree script allows you to add custom key mappings and menu items via
a set of API calls. Any scripts that use this API should be placed in
~/.vim/nerdtree_plugin/ (*nix) or ~/vimfiles/nerdtree_plugin (windows).

The script exposes some prototype objects that can be used to manipulate the
tree and/or get information from it: >
    g:NERDTreePath
    g:NERDTreeDirNode
    g:NERDTreeFileNode
    g:NERDTreeBookmark
<
See the code/comments in NERD_tree.vim to find how to use these objects. The
following code conventions are used:
    * class members start with a capital letter
    * instance members start with a lower case letter
    * private members start with an underscore

See this blog post for more details:
 http://got-ravings.blogspot.com/2008/09/vim-pr0n-prototype-based-objects.html

------------------------------------------------------------------------------
4.1. Key map API                                           *NERDTreeKeymapAPI*

NERDTreeAddKeyMap({options})                             *NERDTreeAddKeyMap()*
    Adds a new keymapping for all NERD tree buffers.
    {options} must be a dictionary, and must contain the following keys:
    "key" - the trigger key for the new mapping
    "callback" - the function the new mapping will be bound to
    "quickhelpText" - the text that will appear in the quickhelp (see
    |NERDTree-?|)

    Example: >
        call NERDTreeAddKeyMap({
               \ 'key': 'b',
               \ 'callback': 'NERDTreeEchoCurrentNode',
               \ 'quickhelpText': 'echo full path of current node' })

        function! NERDTreeEchoCurrentNode()
            let n = g:NERDTreeFileNode.GetSelected()
            if n != {}
                echomsg 'Current node: ' . n.path.str()
            endif
        endfunction
<
    This code should sit in a file like ~/.vim/nerdtree_plugin/mymapping.vim.
    It adds a (rather useless) mapping on 'b' which echos the full path to the
    current node.

------------------------------------------------------------------------------
4.2. Menu API                                                *NERDTreeMenuAPI*

NERDTreeAddSubmenu({options})                           *NERDTreeAddSubmenu()*
    Creates and returns a new submenu.

    {options} must be a dictionary and must contain the following keys:
    "text" - the text of the submenu that the user will see
    "shortcut" - a shortcut key for the submenu (need not be unique)

    The following keys are optional:
    "isActiveCallback" - a function that will be called to determine whether
    this submenu item will be displayed or not. The callback function must return
    0 or 1.
    "parent" - the parent submenu of the new submenu (returned from a previous
    invocation of NERDTreeAddSubmenu()). If this key is left out then the new
    submenu will sit under the top level menu.

    See below for an example.

NERDTreeAddMenuItem({options})                         *NERDTreeAddMenuItem()*
    Adds a new menu item to the NERD tree menu (see |NERDTreeMenu|).

    {options} must be a dictionary and must contain the
    following keys:
    "text" - the text of the menu item which the user will see
    "shortcut" - a shortcut key for the menu item (need not be unique)
    "callback" - the function that will be called when the user activates the
    menu item.

    The following keys are optional:
    "isActiveCallback" - a function that will be called to determine whether
    this menu item will be displayed or not. The callback function must return
    0 or 1.
    "parent" - if the menu item belongs under a submenu then this key must be
    specified. This value for this key will be the object that
    was returned when the submenu was created with |NERDTreeAddSubmenu()|.

    See below for an example.

NERDTreeAddMenuSeparator([{options}])             *NERDTreeAddMenuSeparator()*
    Adds a menu separator (a row of dashes).

    {options} is an optional dictionary that may contain the following keys:
    "isActiveCallback" - see description in |NERDTreeAddMenuItem()|.

Below is an example of the menu API in action. >
    call NERDTreeAddMenuSeparator()

    call NERDTreeAddMenuItem({
                \ 'text': 'a (t)op level menu item',
                \ 'shortcut': 't',
                \ 'callback': 'SomeFunction' })

    let submenu = NERDTreeAddSubmenu({
                \ 'text': 'a (s)ub menu',
                \ 'shortcut': 's' })

    call NERDTreeAddMenuItem({
                \ 'text': '(n)ested item 1',
                \ 'shortcut': 'n',
                \ 'callback': 'SomeFunction',
                \ 'parent': submenu })

    call NERDTreeAddMenuItem({
                \ 'text': '(n)ested item 2',
                \ 'shortcut': 'n',
                \ 'callback': 'SomeFunction',
                \ 'parent': submenu })
<
This will create the following menu: >
  --------------------
  a (t)op level menu item
  a (s)ub menu
<
Where selecting "a (s)ub menu" will lead to a second menu: >
  (n)ested item 1
  (n)ested item 2
<
When any of the 3 concrete menu items are selected the function "SomeFunction"
will be called.

------------------------------------------------------------------------------
NERDTreeRender()                                            *NERDTreeRender()*
    Re-renders the NERD tree buffer. Useful if you change the state of the
    tree and you want to it to be reflected in the UI.

==============================================================================
5. About                                                       *NERDTreeAbout*

The author of the NERD tree is a terrible terrible monster called Martyzilla
who gobbles up small children with milk and sugar for breakfast.

He can be reached at martin.grenfell at gmail dot com. He would love to hear
from you, so feel free to send him suggestions and/or comments about this
plugin.  Don't be shy --- the worst he can do is slaughter you and stuff you in
the fridge for later ;)

The latest stable versions can be found at
    http://www.vim.org/scripts/script.php?script_id=1658

The latest dev versions are on github
    http://github.com/scrooloose/nerdtree


==============================================================================
6. Changelog                                               *NERDTreeChangelog*

4.x.x
    - Fix a bug with :NERDTreeFind and symlinks. Thanks to Vitaly Bogdanov.

4.1.0
    features:
    - NERDTreeFind to reveal the node for the current buffer in the tree,
      see |NERDTreeFind|. This effectively merges the FindInNERDTree plugin (by
      Doug McInnes) into the script.
    - make NERDTreeQuitOnOpen apply to the t/T keymaps too. Thanks to Stefan
      Ritter and Rémi Prévost.
    - truncate the root node if wider than the tree window. Thanks to Victor
      Gonzalez.

    bugfixes:
    - really fix window state restoring
    - fix some win32 path escaping issues. Thanks to Stephan Baumeister, Ricky,
      jfilip1024, and Chris Chambers

4.0.0
    - add a new programmable menu system (see :help NERDTreeMenu).
    - add new APIs to add menus/menu-items to the menu system as well as
      custom key mappings to the NERD tree buffer (see :help NERDTreeAPI).
    - removed the old API functions
    - added a mapping to maximize/restore the size of nerd tree window, thanks
      to Guillaume Duranceau for the patch. See :help NERDTree-A for details.

    - fix a bug where secondary nerd trees (netrw hijacked trees) and
      NERDTreeQuitOnOpen didnt play nicely, thanks to Curtis Harvey.
    - fix a bug where the script ignored directories whose name ended in a dot,
      thanks to Aggelos Orfanakos for the patch.
    - fix a bug when using the x mapping on the tree root, thanks to Bryan
      Venteicher for the patch.
    - fix a bug where the cursor position/window size of the nerd tree buffer
      wasnt being stored on closing the window, thanks to Richard Hart.
    - fix a bug where NERDTreeMirror would mirror the wrong tree

3.1.1
    - fix a bug where a non-listed no-name buffer was getting created every
      time the tree windows was created, thanks to Derek Wyatt and owen1
    - make <CR> behave the same as the 'o' mapping
    - some helptag fixes in the doc, thanks strull
    - fix a bug when using :set nohidden and opening a file where the previous
      buf was modified. Thanks iElectric
    - other minor fixes

3.1.0
    New features:
    - add mappings to open files in a vsplit, see :help NERDTree-s and :help
      NERDTree-gs
    - make the statusline for the nerd tree window default to something
      hopefully more useful. See :help 'NERDTreeStatusline'
    Bugfixes:
    - make the hijack netrw functionality work when vim is started with "vim
      <some dir>" (thanks to Alf Mikula for the patch).
    - fix a bug where the CWD wasnt being changed for some operations even when
      NERDTreeChDirMode==2 (thanks to Lucas S. Buchala)
    - add -bar to all the nerd tree :commands so they can chain with other
      :commands (thanks to tpope)
    - fix bugs when ignorecase was set (thanks to nach)
    - fix a bug with the relative path code (thanks to nach)
    - fix a bug where doing a :cd would cause :NERDTreeToggle to fail (thanks nach)


3.0.1
    Bugfixes:
    - fix bugs with :NERDTreeToggle and :NERDTreeMirror when 'hidden
      was not set
    - fix a bug where :NERDTree <path> would fail if <path> was relative and
      didnt start with a ./ or ../  Thanks to James Kanze.
    - make the q mapping work with secondary (:e <dir>  style) trees,
      thanks to jamessan
    - fix a bunch of small bugs with secondary trees

    More insane refactoring.

3.0.0
    - hijack netrw so that doing an :edit <directory>  will put a NERD tree in
      the window rather than a netrw browser. See :help 'NERDTreeHijackNetrw'
    - allow sharing of trees across tabs, see :help :NERDTreeMirror
    - remove "top" and "bottom" as valid settings for NERDTreeWinPos
    - change the '<tab>' mapping to 'i'
    - change the 'H' mapping to 'I'
    - lots of refactoring

==============================================================================
7. Credits                                                   *NERDTreeCredits*

Thanks to the following people for testing, bug reports, ideas etc. Without
you I probably would have got bored of the hacking the NERD tree and
just downloaded pr0n instead.

    Tim Carey-Smith (halorgium)
    Vigil
    Nick Brettell
    Thomas Scott Urban
    Terrance Cohen
    Yegappan Lakshmanan
    Jason Mills
    Michael Geddes (frogonwheels)
    Yu Jun
    Michael Madsen
    AOYAMA Shotaro
    Zhang Weiwu
    Niels Aan de Brugh
    Olivier Yiptong
    Zhang Shuhan
    Cory Echols
    Piotr Czachur
    Yuan Jiang
    Matan Nassau
    Maxim Kim
    Charlton Wang
    Matt Wozniski (godlygeek)
    knekk
    Sean Chou
    Ryan Penn
    Simon Peter Nicholls
    Michael Foobar
    Tomasz Chomiuk
    Denis Pokataev
    Tim Pope (tpope)
    James Kanze
    James Vega (jamessan)
    Frederic Chanal (nach)
    Alf Mikula
    Lucas S. Buchala
    Curtis Harvey
    Guillaume Duranceau
    Richard Hart (hates)
    Doug McInnes
    Stefan Ritter
    Rémi Prévost
    Victor Gonzalez
    Stephan Baumeister
    Ricky
    jfilip1024
    Chris Chambers
    Vitaly Bogdanov

==============================================================================
8. License                                                   *NERDTreeLicense*

The NERD tree is released under the wtfpl.
See http://sam.zoy.org/wtfpl/COPYING.