A better Emacs *help* buffer
Emacs Lisp Shell
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Latest commit 07fd87c Jul 8, 2018

README.md

Helpful Build Status Coverage Status MELPA

Helpful is an alternative to the built-in Emacs help that provides much more contextual information.

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Usage

Install from MELPA, then call one of the following commands:

  • helpful-callable
  • helpful-function
  • helpful-macro
  • helpful-command
  • helpful-key
  • helpful-variable
  • helpful-at-point

If you want to replace the default Emacs help keybindings, you can do so:

;; Note that the built-in `describe-function' includes both functions
;; and macros. `helpful-function' is functions only, so we provide
;; `helpful-callable' as a drop-in replacement.
(global-set-key (kbd "C-h f") #'helpful-callable)

(global-set-key (kbd "C-h v") #'helpful-variable)
(global-set-key (kbd "C-h k") #'helpful-key)

I also recommend the following keybindings to get the most out of helpful:

;; Lookup the current symbol at point. C-c C-d is a common keybinding
;; for this in lisp modes.
(global-set-key (kbd "C-c C-d") #'helpful-at-point)

;; Look up *F*unctions (excludes macros).
;;
;; By default, C-h F is bound to `Info-goto-emacs-command-node'. Helpful
;; already links to the manual, if a function is referenced there.
(global-set-key (kbd "C-h F") #'helpful-function)

;; Look up *C*ommands.
;;
;; By default, C-h C is bound to describe `describe-coding-system'. I
;; don't find this very useful, but it's frequently useful to only
;; look at interactive functions.
(global-set-key (kbd "C-h C") #'helpful-command)

Features

Source code

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Helpful will try really hard to show the source code. It shows the source code for interactively defined functions (unlike the built-in Help) and falls back to the raw sexp if no source is available.

View Callers

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Helpful will show you where a function is being called!

Prettier Docstrings

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Docstrings in helpful:

  • Highlight the summary (the first sentence)
  • Include cross-references to other functions/variables
  • Linkify references to Info nodes
  • Hide superfluous punctuation

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If a symbol is also documented in the Info manual, helpful will provide a link to the relevant section too.

Symbol Properties

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Helpful will show you the properties that have been applied to the current symbol. This provides visibility of features like edebug or byte-code optimisation.

Helpful will also highlight any symbol aliases.

Describe Commands

Helpful provides a separate helpful-command function, for when you just want to view interactive functions.

View Keymaps

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Helpful displays any keybindings that apply to interactive functions.

Integrated Tooling

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You can trace, debug or disassemble functions from inside Helpful. This is discoverable and doesn't require memorisation of commands.

Aliases

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If a function has multiple aliases in Emacs, Helpful will show all of the aliases defined.

Inspirations

This project has been heavily influenced by: