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* Names [[https://travis-ci.org/Bruce-Connor/names?branch=master][https://secure.travis-ci.org/Bruce-Connor/names.png?branch=master]]

*Names* is designed as a practical, complete, robust, and debuggable
tool which writes your namespaces for you.

It is part of Emacs and is available trough [[https://elpa.gnu.org/packages/names.html][GNU Elpa]], so every
Emacs user running at least 24.1 has access to it.

[[file:package-example.png]]\\
/Example usage of Names to namespace an emacs-lisp function./
*** A Namespace implementation for Emacs-Lisp

The *Names* package aims to provide an implementation of
namespaces in Emacs with four guiding principles:

- Practical :: Actually useful and easy to grasp.
- Complete :: Support any macro, function, or special-form available in
              emacs-lisp, /even/ the ones defined by you or a third
              party.
- Robust :: No-surprises, well-tested, and with clearly stated
            limitations.
- Debuggable :: Support *edebug* and =eval-defun=, and any other
                package developing tools.

See [[https://github.com/Bruce-Connor/spaces#why-a-namespace-package][Why a namespace package?]] for a description on why this is
necessary, and see [[https://github.com/Bruce-Connor/emacs-lisp-namespaces/blob/master/Other-Packages.org][Other-Packages.org]] for a description and comparison
of previous packages attempting similar things.

**** Version Compatibility
Currently, *Names* is being supported on the entire Emacs 24 family
(24.1--24.4). Any new changes or pull requests are tested on a
[[https://travis-ci.org/Bruce-Connor/names][Travis-CI machine]]. See the /“tests”/ subdirectory for our test suite,
and see .

** Usage
The [[https://github.com/Bruce-Connor/emacs-lisp-namespaces/blob/master/UsageExample.org][UsageExample]] file clearly displays and explains how to use *Names*
in your package. There are few simple measures to take. Go have a look
if you’re interested, I promise it’s worth it!

If you want deeper descriptions of use-cases, see [[https://github.com/Bruce-Connor/emacs-lisp-namespaces/blob/master/TheNittyGritty.org][TheNittyGritty.org]].

** Developer Tools
*Names* offers a series of tools to make package writing more
convenient inside a namespace. These developer facilities are on this
separate file, so the file isn't loaded on the user's computer when
your package calls =(require 'names)=.

To access them add the following line to your init file.
#+begin_src emacs-lisp
(require 'names-dev)
#+end_src

*** Edebug and eval-defun support

First and foremost, the =edebug-eval-defun= command (bound to =C-u
C-M-x=) is an essential tool for any package developer. *Names*
wouldn't be a very useful utility if it prevented you from using this
asset. 

Therefore, it provides the =names-eval-defun= command, which is
identical to =edebug-eval-defun= except it also works inside
namespaces. It will automatically be added to your
=emacs-lisp-mode-map=.

*** Font-locking 
Font-lock for =define-namespace= and =:autoload=.

*** Expansion and comparison functions
=names-compare-forms= and =names-print= offer information when
something just doesn't seem to make sense.

** Nomenclature

The name of this package is *Names*, always with a capital “N”.
Despite the word being plural, refer to it in the singular (e.g.,
“Names is an amazing achievement”). If possible consider giving it a
slight emphasis, such as: /Names/.
When there's a risk of confusion or ambiguity, be it due to context or
lack of knowledge by the reader, =names.el= is also acceptable.

** Why a namespace package?
Plain and simple: Emacs doesn't have namespaces, and it needs them.

Nic Ferrier has a [[http://nic.ferrier.me.uk/blog/2013_06/adding-namespaces-to-elisp][great essay on the subject]], and you might want to
read [[https://lists.gnu.org/archive/html/emacs-devel/2014-12/msg00772.html][an opposing opinion]] as well. Note that *Names* is very different
from the solution he proposes, but it does solve the problem he had
with other alternatives which left the debugger unusable.

Emacs takes the approach of prefixing every symbol name with the name
of the package. This successfully avoids name clashes between
packages, but it quickly leads to code that's repetitive and annoying
to write. Below is an example from =package.el=, the word "/package/"
is repeated 7 times in a 10-line function.

*Names* doesn't change this overall approach. It adheres to Emacs
standards and is completely invisible to the end-user. *Names* simply
gives /you/ (the developer) a convenient way of writing code that
adheres to this standard.

[[file:package-example.png]]
/Example usage of Names to namespace an emacs-lisp function./

- At runtime, the right-hand-side will create the same definitions as the left-hand-side.
- At compilation, it will create the exact same compiled file (with no left-over reference to =names.el= functions).

*** Tested On:
Below are the packages on which I've tested *Names*. If you're
interested, try using it on one of your packages and [[https://github.com/Bruce-Connor/names/issues][let me know how
it goes]].
**** elnode
- *Number of ert tests passed:* Same as before namespacing (62).
- *Reduction in code size:* Approx. 2000 characters.
**** s.el
- *Number of ert tests passed:* All.
- *Reduction in code size:* Approx. 1000 characters (8%). 
1000 characters is a lot when you consider /s.el/ has the second
shortest namespace possible, =s-=.
**** dash.el
- *Number of ert tests passed:* Same as before namespacing (104).
**** latex-extra
- *Number of ert tests passed:* ALL.
**** aggressive-indent
No actual tests defined, but this package actually uses /Names/ for
real! And it's alive and well.