vim-erlang-tags

Table of Contents

• The idea
• Installation
• Usage
  • Generate tags
  • Options
    • g:erlang_tags_ignore
    • g:erlang_tags_auto_update
    • g:erlang_tags_auto_update_current
    • g:erlang_tags_outfile
    • g:erlang_tags_follow
    • g:erlang_tags_otp
  • Automating generating tags
  • Make Vim use the tags
  • Using the Vim tag search commands
• Contributing

The idea

vim-erlang-tags creates a tags file (from Erlang source files), which can be used by Vim.

When using Exuberant ctags or etags, the generated tags will contain function names, but there will be no module:function tags. This is a problem because if several functions (in different modules) have the same name, the text editor will not know which one to jump to.

The idea of this script is to generate module:function tags too. This way the code will be easier to navigate than with ctags or etags. The original idea is from László Lövei.

Since : is not a keyword character when editing Erlang files in Vim, this repository also contains a Vim plugin, which modifies the following normal mode commands to add : to the iskeyword option for Erlang files while they are jumping to the location of the tag that is under the cursor:

CTRL-]
g<LeftMouse>
<C-LeftMouse>
g]
g CTRL-]

Installation

Usage

Let's say you would like to use tags for your Erlang project.

Generate tags

First you need to generate the tags.

You can do that either in the command line:

$ cd /path/to/my_erlang_project
$ /path/to/vim-erlang-tags/bin/vim_erlang_tags.erl

Or within Vim by executing the following command:

:ErlangTags

Note that for the latter command, the current working directory will be used (:help pwd to find out more).

Options

g:erlang_tags_ignore

Add ignore path for tags generation. Use a string or list of strings like:

    let g:erlang_tags_ignore = 'rel'
    let g:erlang_tags_ignore = ['rel']

Default: doesn't exist.

g:erlang_tags_auto_update

If exists and set to 1, this plugin will be triggered when an Erlang buffer is written. Warning: this may cost lots of CPU if you have a large project. Note that it might not work on Windows.

Default: doesn't exist.

g:erlang_tags_auto_update_current

If exists and set to 1, this plugin will be triggered when an Erlang buffer is written. In this case, it will attempt to update only the currently modified file. As a limitation, this will consider that your tags file is on the current directory, as returned by vim's getcwd(). Note that it might not work on Windows.

Default: doesn't exist.

g:erlang_tags_outfile

This option specifies the name of the generated tags file. By default, the output file will be ./tags.

g:erlang_tags_follow

If exists and set to 1, this plugin will follow symbolic links.

Default: doesn't follow symbolic links.

g:erlang_tags_otp

If exists and set to 1, this plugin will include the currently used OTP lib_dir.

Default: doesn't include OTP lib_dir.

Automating generating tags

To keep the tags file up-to-date you can re-run these commands periodically, or automate the process by creating a commit/checkout hook or a crontab entry.

If you use Git, creating a checkout hook is simple:

echo '#!/bin/bash' > .git/hooks/post-checkout
echo '/path/to/vim-erlang-tags/bin/vim_erlang_tags.erl' > .git/hooks/post-checkout
chmod +x .git/hooks/post-checkout
cp -i .git/hooks/post-checkout .git/hooks/post-commit

Make Vim use the tags

Add the following line to your .vimrc:

:set tags^=/path/to/my_erlang_project/tags

This will explicitly add the tags file to the list of known tags locations.

Reopen Vim or just execute :source $MYVIMRC – now all your function names, records, macros and file names are available with the Vim tag search commands.

Using the Vim tag search commands

The few most useful tag search commands are the following:

• CTRL-]: jump to the definition of the function/record/macro under the cursor
• :tj ident: jump to the definition of ident (function/record/macro name)

For more information on those commands, see :help tagsrch.txt.

Contributing

• Please read the Contributing section of the vim-erlang README.

• If you modify vim_erlang_tags.erl, please update the tests in in the vim-erlang repository.