━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ PULSAR.EL: PULSE HIGHLIGHT LINE ON DEMAND OR AFTER RUNNING SELECT FUNCTIONS Protesilaos Stavrou info@protesilaos.com ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ This manual, written by Protesilaos Stavrou, describes the customization options for `pulsar' (or `pulsar.el'), and provides every other piece of information pertinent to it. The documentation furnished herein corresponds to stable version 0.5.0, released on 2022-08-19. Any reference to a newer feature which does not yet form part of the latest tagged commit, is explicitly marked as such. Current development target is 0.6.0-dev. ⁃ Package name (GNU ELPA): `pulsar' ⁃ Official manual: ⁃ Change log: ⁃ Git repo on SourceHut: • Mirrors: ⁃ GitHub: ⁃ GitLab: ⁃ Mailing list: Table of Contents ───────────────── 1. COPYING 2. Overview .. 1. Convenience functions 3. Installation .. 1. GNU ELPA package .. 2. Manual installation 4. Sample configuration .. 1. Use pulsar with next-error 5. Integration with other packages 6. Acknowledgements 7. GNU Free Documentation License 8. Indices .. 1. Function index .. 2. Variable index .. 3. Concept index 1 COPYING ═════════ Copyright (C) 2022 Free Software Foundation, Inc. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, with the Front-Cover Texts being “A GNU Manual,” and with the Back-Cover Texts as in (a) below. A copy of the license is included in the section entitled “GNU Free Documentation License.” (a) The FSF’s Back-Cover Text is: “You have the freedom to copy and modify this GNU manual.” 2 Overview ══════════ This is a small package that temporarily highlights the current line after a given function is invoked. The affected functions are defined in the user option `pulsar-pulse-functions' and the effect takes place when either `pulsar-mode' (buffer-local) or `pulsar-global-mode' is enabled. The overall duration of the highlight is determined by a combination of `pulsar-delay' and `pulsar-iterations'. The latter determines the number of blinks in a pulse, while the former sets their delay in seconds before they fade out. The applicable face is specified in `pulsar-face'. To disable the pulse but keep the temporary highlight, set the user option `pulsar-pulse' to nil. The current line will remain highlighted until another command is invoked. To highlight the current line on demand, use the `pulsar-pulse-line' command. When `pulsar-pulse' is non-nil (the default), its highlight will pulse before fading away. Whereas the `pulsar-highlight-line' command never pulses the line: the highlight stays in place as if `pulsar-pulse' is nil. A do-what-I-mean command is also on offer: `pulsar-highlight-dwim'. It highlights the current line line like `pulsar-highlight-line'. If the region is active, it applies its effect there. The region may also be a rectangle (internally they differ from ordinary regions). To help users differentiate between the pulse and highlight effects, the user option `pulsar-highlight-face' controls the presentation of the `pulsar-highlight-line' and `pulsar-highlight-dwim' commands. By default, this variable is the same as `pulsar-face'. Pulsar depends on the built-in `pulse.el' library. Why the name “pulsar”? It sounds like “pulse” and is a recognisable word. Though if you need a backronym, consider “Pulsar Unquestionably Luminates, Strictly Absent the Radiation”. 2.1 Convenience functions ───────────────────────── Depending on the user’s workflow, there may be a need for differently colored pulses. These are meant to provide an ad-hoc deviation from the standard style of the command `pulsar-pulse-line' (which is governed by the user option `pulsar-face'). Pulsar thus provides the following for the user’s convenience: • `pulsar-pulse-line-red' • `pulsar-pulse-line-green' • `pulsar-pulse-line-yellow' • `pulsar-pulse-line-blue' • `pulsar-pulse-line-magenta' • `pulsar-pulse-line-cyan' These can be called with `M-x', assigned to a hook and/or key binding, or be incorporated in custom functions. 3 Installation ══════════════ 3.1 GNU ELPA package ──────────────────── The package is available as `pulsar'. Simply do: ┌──── │ M-x package-refresh-contents │ M-x package-install └──── And search for it. GNU ELPA provides the latest stable release. Those who prefer to follow the development process in order to report bugs or suggest changes, can use the version of the package from the GNU-devel ELPA archive. Read: . 3.2 Manual installation ─────────────────────── Assuming your Emacs files are found in `~/.emacs.d/', execute the following commands in a shell prompt: ┌──── │ cd ~/.emacs.d │ │ # Create a directory for manually-installed packages │ mkdir manual-packages │ │ # Go to the new directory │ cd manual-packages │ │ # Clone this repo, naming it "pulsar" │ git clone https://git.sr.ht/~protesilaos/pulsar pulsar └──── Finally, in your `init.el' (or equivalent) evaluate this: ┌──── │ ;; Make Elisp files in that directory available to the user. │ (add-to-list 'load-path "~/.emacs.d/manual-packages/pulsar") └──── Everything is in place to set up the package. 4 Sample configuration ══════════════════════ Remember to read the doc string of each of these variables. ┌──── │ (require 'pulsar) │ │ ;; Check the default value of `pulsar-pulse-functions'. That is where │ ;; you add more commands that should cause a pulse after they are │ ;; invoked │ │ (setq pulsar-pulse t) │ (setq pulsar-delay 0.055) │ (setq pulsar-iterations 10) │ (setq pulsar-face 'pulsar-magenta) │ (setq pulsar-highlight-face 'pulsar-yellow) │ │ (pulsar-global-mode 1) │ │ ;; OR use the local mode for select mode hooks │ │ (dolist (hook '(org-mode-hook emacs-lisp-mode-hook)) │ (add-hook hook #'pulsar-mode)) │ │ ;; pulsar does not define any key bindings. This is just a sample that │ ;; respects the key binding conventions. Evaluate: │ ;; │ ;; (info "(elisp) Key Binding Conventions") │ ;; │ ;; The author uses C-x l for `pulsar-pulse-line' and C-x L for │ ;; `pulsar-highlight-line'. │ ;; │ ;; You can replace `pulsar-highlight-line' with the command │ ;; `pulsar-highlight-dwim'. │ (let ((map global-map)) │ (define-key map (kbd "C-c h p") #'pulsar-pulse-line) │ (define-key map (kbd "C-c h h") #'pulsar-highlight-line)) └──── 4.1 Use pulsar with next-error ────────────────────────────── By default, the `n' and `p' keys in Emacs’ compilation buffers (e.g. the results of a `grep' search) produce a highlight for the locus of the given match. Due to how the code is implemented, we cannot use Pulsar’s standard mechanism to trigger a pulse after the match is highlighted. Instead, the user must add this to their configuration in lieu of a Pulsar-level solution that “just works”: ┌──── │ (add-hook 'next-error-hook #'pulsar-pulse-line) └──── 5 Integration with other packages ═════════════════════════════════ Beside `pulsar-pulse-line', Pulsar defines a few functions that can be added to hooks that are provided by other packages. There are two functions to recenter and then pulse the current line: `pulsar-recenter-top' and `pulsar-recenter-middle'. There also exists `pulsar-reveal-entry' which displays the hidden contents of an Org or Outline heading. It can be used in tandem with the aforementioned recentering functions. Example use-cases: ┌──── │ ;; integration with the `consult' package: │ (add-hook 'consult-after-jump-hook #'pulsar-recenter-top) │ (add-hook 'consult-after-jump-hook #'pulsar-reveal-entry) │ │ ;; integration with the built-in `imenu': │ (add-hook 'imenu-after-jump-hook #'pulsar-recenter-top) │ (add-hook 'imenu-after-jump-hook #'pulsar-reveal-entry) └──── 6 Acknowledgements ══════════════════ Pulsar is meant to be a collective effort. Every bit of help matters. Author/maintainer Protesilaos Stavrou. Contributions to the code or manual Aymeric Agon-Rambosson, Daniel Mendler, Ivan Popovych, JD Smith. Ideas and user feedback Duy Nguyen, Mark Barton, Petter Storvik, Rudolf Adamkovič, Toon Claes, and users djl, kb. 7 GNU Free Documentation License ════════════════════════════════ 8 Indices ═════════ 8.1 Function index ────────────────── 8.2 Variable index ────────────────── 8.3 Concept index ─────────────────