/beancount-mode

Emacs major-mode to work with Beancount ledger files

Primary LanguageEmacs LispGNU General Public License v3.0GPL-3.0

Emacs major-mode to work with Beancount ledger files

This package provides beancount-mode an Emacs major-mode implementing syntax highlighting, indentation, completion , and other facilities to edit and work with Beancount ledger files.

To instruct Emacs to activate beancount-mode when opening files with a .beancount extension, you can add this code to your Emacs configuration, typically in the ~/.emacs.d/init.el file:

(add-to-list 'load-path "/path/to/beancount-mode/")
(require 'beancount)
(add-to-list 'auto-mode-alist '("\\.beancount\\'" . beancount-mode))

Most facilities commonly provided by Emacs major modes are implemented by beancount-mode. Documentation on the provided functionality and on the default keybindings can be obtained with the describe-mode command in a buffer with beancount-mode active.

In a nutshell, when beancount-mode is active:

  • The “TAB” key either indents, completes, or folds the heading at point, depending on the context.
  • Amounts in postings are indented so that the decimal point is at the beancount-number-alignment-column column. Setting this variable to 0 will cause the alignment column to be determined from file content.
  • Postings in transactions, as well as metadata, links, and tags following directives, and are indented with beancount-transaction-indent spaces.
  • Pressing the “RET” key causes the current line to be automatically indented. If the current line is a posting, the amount will be indented as described above.

The automatic indentation behavior is defined by Emacs auto indent mechanism, however, it can be surprising or undesired. It can be disabled setting electric-indent-chars to nil after loading beancount-mode, for example like this:

(add-hook 'beancount-mode-hook
  (lambda () (setq-local electric-indent-chars nil)))

Beancount ledger files can grow very large. It is thus often practical to structure them in sections and subsections. To support this, beancount-mode leverages Outline minor-mode to enable navigation of the document structure to fold and unfold the document sections, similarly to what is possible in Org mode. Lines starting with one asterisks ”*” or three or more semicolons ”;;;” are interpreted as section headings. In Beancount, the semicolon starts a comment and all lines starting with an asterisks are ignored. The number of semicolons or asterisks determines the heading level.

To enable this functionality, outline-minor-mode should be explicitly activated. It is possible to do so automatically when beancout-mode is activated:

(add-hook 'beancount-mode-hook #'outline-minor-mode)

Outline minor mode uses a rather peculiar choice of keybindings. It is possible to map the most used functionality to keys more familiar to org-mode users adding a few lines to the Emacs configuration:

(define-key beancount-mode-map (kbd "C-c C-n") #'outline-next-visible-heading)
(define-key beancount-mode-map (kbd "C-c C-p") #'outline-previous-visible-heading)

Alternatively the keybindings for outline-minor-mode can be globally remapped. Please refer to the outline-minor-mode documentation in the Emacs manual for more details.

The etc/emacsrc file contains some example configuration for beancount-mode and some experiments that may find their way into the main codebase.