Homepage: https://github.com/magnars/expand-region.el
Author: Magnar Sveen
Updated:
Increase selected region by semantic units
Expand region increases the selected region by semantic units. Just keep
pressing the key until it selects what you want.
An example:
(setq alphabet-start "abc def")
With the cursor at the `c`, it starts by marking the entire word `abc`, then
expand to the contents of the quotes `abc def`, then to the entire quote
`"abc def"`, then to the contents of the sexp `setq alphabet-start "abc def"`
and finally to the entire sexp.
You can set it up like this:
(require 'expand-region)
(global-set-key (kbd "C-=") 'er/expand-region)
There's also `er/contract-region` if you expand too far.
## Video
You can [watch an intro to expand-region at Emacs Rocks](http://emacsrocks.com/e09.html).
## Language support
Expand region works fairly well with most languages, due to the general
nature of the basic expansions:
er/mark-word
er/mark-symbol
er/mark-method-call
er/mark-inside-quotes
er/mark-outside-quotes
er/mark-inside-pairs
er/mark-outside-pairs
However, most languages also will benefit from some specially crafted
expansions. For instance, expand-region comes with these extra expansions for
html-mode:
er/mark-html-attribute
er/mark-inner-tag
er/mark-outer-tag
You can add your own expansions to the languages of your choice simply by
creating a function that looks around point to see if it's inside or looking
at the construct you want to mark, and if so - mark it.
There's plenty of examples to look at in these files.
After you make your function, add it to a buffer-local version of
the `er/try-expand-list`.
**Example:**
Let's say you want expand-region to also mark paragraphs and pages in
text-mode. Incidentally Emacs already comes with `mark-paragraph` and
`mark-page`. To add it to the try-list, do this:
(defun er/add-text-mode-expansions ()
(make-variable-buffer-local 'er/try-expand-list)
(setq er/try-expand-list (append
er/try-expand-list
'(mark-paragraph
mark-page))))
(er/enable-mode-expansions 'text-mode 'er/add-text-mode-expansions)
Add that to its own file, and require it at the bottom of this one,
where it says "Mode-specific expansions"
**Warning:** Badly written expansions might slow down expand-region
dramatically. Remember to exit quickly before you start traversing
the entire document looking for constructs to mark.
## Contribute
If you make some nice expansions for your favorite mode, it would be
great if you opened a pull-request. The repo is at:
https://github.com/magnars/expand-region.el
Changes to `expand-region-core` itself must be accompanied by feature tests.
They are written in [Ecukes](http://ecukes.info), a Cucumber for Emacs.
To fetch the test dependencies:
$ cd /path/to/expand-region
$ git submodule init
$ git submodule update
Run the tests with:
$ ./util/ecukes/ecukes features
If you want to add feature-tests for your mode-specific expansions as well,
that is utterly excellent.
## Contributors
* [Josh Johnston](https://github.com/joshwnj) contributed `er/contract-region`
* [Le Wang](https://github.com/lewang) contributed consistent handling of the mark ring, expanding into pairs/quotes just left of the cursor, and general code clean-up.
* [Matt Briggs](https://github.com/mbriggs) contributed expansions for ruby-mode.
* [Ivan Andrus](https://github.com/gvol) contributed expansions for python-mode, text-mode, LaTeX-mode and nxml-mode.
* [Raimon Grau](https://github.com/kidd) added support for when transient-mark-mode is off.
* [Gleb Peregud](https://github.com/gleber) contributed expansions for erlang-mode.
* [fgeller](https://github.com/fgeller) and [edmccard](https://github.com/edmccard) contributed better support for python and its multiple modes.
* [François Févotte](https://github.com/ffevotte) contributed expansions for C and C++.
* [Roland Walker](https://github.com/rolandwalker) added option to copy the contents of the most recent action to a register, and some fixes.
* [Damien Cassou](https://github.com/DamienCassou) added option to continue expanding/contracting with fast keys after initial expand.
Thanks!