d12frosted / prescient.el

☄️ Simple but effective sorting and filtering for Emacs.

prescient.el: simple but effective sorting and filtering for Emacs.

Summary

prescient.el is a library which sorts and filters lists of candidates, such as appear when you use a package like Ivy or Company. Extension packages such as ivy-prescient.el and company-prescient.el adapt the library for usage with various frameworks.

As compared to other packages which accomplish similar tasks, including IDO, Ivy, Helm, Smex, Flx, Historian, and Company-Statistics, prescient.el aims to be simpler, more predictable, and faster.

Installation

prescient.el is available on MELPA as four separate packages (one for the library, and the rest for integrating with other frameworks):

• prescient
• ivy-prescient
• company-prescient
• selectrum-prescient

The easiest way to install these packages is using straight.el:

(straight-use-package 'prescient)
(straight-use-package 'ivy-prescient)
(straight-use-package 'company-prescient)
(straight-use-package 'selectrum-prescient)

However, you may install using any other package manager if you prefer.

Usage

• To cause Ivy to use prescient.el sorting and filtering, enable ivy-prescient-mode.
• To cause Company to use prescient.el sorting, enable company-prescient-mode.
• To cause Selectrum to use prescient.el sorting and filtering, enable selectrum-prescient-mode.
• To cause your usage statistics to be saved between Emacs sessions, enable prescient-persist-mode.

Please note that you must load Counsel before ivy-prescient.el. This is because loading Counsel results in a number of changes being made to the user options of Ivy, which ivy-prescient.el must then undo.

Algorithm

prescient.el takes as input a list of candidates, and a query that you type. The query is first split on spaces into subqueries (two consecutive spaces match a literal space). Each subquery filters the candidates because it must match as either a substring of the candidate, a regexp, or an initialism (e.g. ffap matches find-file-at-point, and so does fa). The last few candidates you selected are displayed first, followed by the most frequently selected ones, and then the remaining candidates are sorted by length. If you don't like the algorithm used for filtering, you can choose a different one by customizing prescient-filter-method.

Configuration

• prescient-history-length: The number of recently selected candidates that are remembered and displayed at the top of the list.

• prescient-frequency-decay: prescient.el keeps a "frequency" for each selected candidate, which is incremented by one each time you select the candidate. To keep things tidy, frequencies are multiplied by this variable's value each time you select a new candidate, so they decrease over time.

• prescient-frequency-threshold: Once the frequency for an infrequently used command falls below the value of this variable, prescient.el forgets about it.

• prescient-save-file: Where to save statistics that are persisted between Emacs sessions when prescient-persist-mode is active. The default value follows the conventions of no-littering.

• prescient-filter-method: A list of algorithms to use for filtering candidates. The default is literal, regexp, and initialism as described above, but you can also use substring matching, initialism matching, regexp matching, fuzzy matching, prefix matching, or any combination of those. See the docstring for full details.

• ivy-prescient-sort-commands: By default, all commands have their candidates sorted. You can override this behavior by customizing ivy-prescient-sort-commands. See the docstring.

• ivy-prescient-retain-classic-highlighting: By default, the highlighting behavior of ivy-prescient.el is slightly different from Ivy's highlighting for ivy--regex-ignore-order. You can recover the original behavior by customizing this user option; see the docstring for more details.

• ivy-prescient-enable-filtering: If set to nil, then ivy-prescient.el does not apply prescient.el filtering to Ivy. See the Ivy documentation for information on how Ivy filters by default, and how to customize it manually.

• ivy-prescient-enable-sorting: If set to nil, then ivy-prescient.el does not apply prescient.el sorting to Ivy. See the Ivy documentation for information on how Ivy sorts by default, and how to customize it manually.

Contributor guide

Please see the contributor guide for my projects.