Overview

Polymode is an emacs package that offers support for multiple major modes inside a single emacs buffer. It is lightweight and fully object oriented, specifically designed for quick addition of new polymodes.

Technically speaking, polymode doesn't keep its modes in a single emacs buffer but in several indirect buffers, actually as many as different modes are there in a file. Consequently, polymode is as fast as switching buffers because it never re-installs major modes. I am very much indebted to Dave Love's multi-mode.el for this awesome idea.

Installation

The project is in an alpha stage and it is not, as yet, available in melpa repo. You will have to install it manually:

git clone https://github.com/vitoshka/polymode.git

Add "polymode" directory and "polymode/modes" to your emacs path:

(setq load-path
      (append '("path/to/polymode/"  "path/to/polymode/modes")
              load-path))

Require any polymode bundles that you are interested in. For example:

(require 'poly-R)
(require 'poly-markdown)

Note that for the full use of poly-markdown modes you will need markdown-mode.el. It is also available from MELPA repository.

Polymodes activation

Polymode defines emacs major and minor modes that you can use in full compliance with emacs usual conventions.

There are two main ways to activate emacs mode.

1. By registering a file extension. Some of the file extensions are already defined for you "Rmd", "Snw", "Rcpp", "cppR", "Rhtml" etc. You can find some examples in tests sub-directory. Of course you can always set your own extensions by adding them to auto-mode-alist.

2. By setting local mode variable in you file. This is how you would activate C++R mode:

// -*- mode: poly-C++R -*-

or

## -*- mode: poly-brew+R; -*-

Warning

• Tested with Emacs 24.3.1 and unlikely to work with Emacses older than 24.2 because of the heavy use of pattern matching and eieio.

Some things still don't work as expected. For example:

• To kill a polymode buffer you will have position the cursor in the base mode buffer.
• Customization interface is not working as expected (an eieio bug) and is not tested.
• No literate programming backends (in the sense of weavers, tanglers and exporters).
• Occasional problems with font-lock. Messages like Error during redisplay: (jit-lock-function 163) signaled (args-out-of-range 1 142) are posible.

Screenshots

Ess-help buffer

C++R

markdown+R

markdown+R+YAML