skim(1)

    Life is short, skim!

Half of our life is spent on navigation: files, lines, commands... You need skim! It is a general fuzzy finder that saves you time.

It is blazingly fast as it reads the data source asynchronously.

skim provides a single executable: sk, basically anywhere you would want to use grep try sk instead.

Usage

skim can be used as a general filter(like grep) or as an interactive interface for invoking commands.

  As filter

Try the following

    # directly invoke skim
    sk
    # or pipe some input to it: (press TAB key select multiple items with -m enabled)
    vim $(find . -name "*.rs" | sk -m)

The above command will allow you to select files with “.rs” extension and open the ones you selected in Vim.

  As Interactive Interface

skim can invoke other commands dynamically. Normally you would want to integrate it with rg (https://github.com/BurntSushi/ripgrep) ag (https://github.com/ggreer/the_silver_searcher) or ack (https://github.com/petdance/ack2) for searching contents in a project directory:

    # work with ag
    sk --ansi -i -c 'ag --color "{}"'
    # or with rg
    sk --ansi -i -c 'rg --color=always --line-number "{}"'

[IMAGE: interactive mode demo (https://cloud.githubusercontent.com/assets/1527040/21603930/655d859a-d1db-11e6-9fec-c25099d30a12.gif)]

  Key Bindings

Some commonly used keybindings:

Key | Action
Enter | Accept (select current one and quit)
ESC/Ctrl-G | Abort
Ctrl-P/Up | Move cursor up
Ctrl-N/Down | Move cursor Down
TAB | Toggle selection and move down (with -m)
Shift-TAB | Toggle selection and move up (with -m)

  Search Syntax

skim borrowed fzf’s syntax for matching items:

Token | Match type | Description
text | fuzzy-match | items that match text
^music | prefix-exact-match | items that start with music
.mp3$ | suffix-exact-match | items that end with .mp3
'wild | exact-match (quoted) | items that include wild
!fire | inverse-exact-match | items that do not include fire
!.mp3$ | inverse-suffix-exact-match | items that do not end with .mp3

skim also supports the combination of tokens.

•   space has the meaning of AND. With the term src main, skim will search for items that match both src and main.

•   | means OR (note the spaces around |). With the term .md$ | .markdown$, skim will search for items ends with either .md or .markdown.

•   OR have higher precedence. So readme .md$ | .markdown$ is groupped into readme AND (.md$ OR .markdown$).

In case that you want to use regular expressions, skim provides regex mode:

    sk --regex

You can switch to regex mode dynamically by pressing Ctrl-R (Rotate Mode).

  exit code

Exit Code | Meaning
0 | Exit normally
1 | No Match found
130 | Abort by Ctrl-C/Ctrl-G/ESC/etc...

Customization

  Keymap

Specify the bindings with comma seperated pairs(no space allowed), example:

sk --bind 'alt-a:select-all,alt-d:deselect-all'

Action | Default key
abort | esc, ctrl-c, ctrl-g
accept | enter
backward-char | left, ctrl-b
backward-delete-char | ctrl-h, backspace
backward-kill-word | alt-backspace
backward-word | alt-b, shift-left
beginning-of-line | ctrl-a
cancel | None
clear-screen | ctrl-l
delete-char | del
delete-charEOF | ctrl-d
deselect-all | None
down | ctrl-j, ctrl-n, down
end-of-line | ctrl-e, end
forward-char | ctrl-f, right
forward-word | alt-f, shift-right
ignore | None
kill-line | ctrl-k
kill-word | alt-d
page-down | page-down
page-up | page-up
rotate-mode | ctrl-r
scroll-left | alt-h
scroll-right | alt-l
select-all | None
toggle | None
toggle-all | None
toggle-down | tab
toggle-interactive | ctrl-q
toggle-out | None
toggle-preview | None
toggle-sort | None
toggle-up | shift-tab
unix-line-discard | ctrl-u
unix-word-rubout | ctrl-w
up | ctrl-p, ctrl-k, up

  Sort Criteria

There are four sort keys for results: score, index, begin, end, you can specify how the records are sorted by sk --tiebreak score,index,-begin or any other order you want.

  Color Scheme

It is a high chance that you are a better artist than me. Luckily you won’t be stuck with the default colors, skim supports customization of the color scheme.

    --color=[BASE_SCHEME][,COLOR:ANSI]

The configuration of colors starts with the name of the base color scheme, followed by custom color mappings. For example:

    sk --color=current_bg:24
    sk --color=light,fg:232,bg:255,current_bg:116,info:27

You can choose the BASE SCHEME among the following(default: dark on 256-color terminal, otherwise 16):

Base Scheme | Description
dark | Color scheme for dark 256-color terminal
light | Color scheme for light 256-color terminal
16 | Color scheme for 16-color terminal
bw | No colors

While the customisable COLORs are

Color | Description
fg | Text
bg | Background
matched | Text color of matched items
matched_bg | Background color of matched items
current | Text color (current line)
current_bg | Background color (current line)
current_match | Text color of matched items (current line)
current_match_bg | Background color of matched items (current line)
spinner | Streaming input indicator
info | Info area
prompt | Prompt
cursor | Cursor
selected | Text color of “selected” indicator
border | Border color of preview window

  Misc

•   --ansi: to parse ANSI color codes(e.g \e[32mABC) of the data source

•   --regex: use the query as regular expression to match the data source

Advanced Topics

  Interactive mode

In interactive mode, sk will pass the query to the command you specified and present the output to you. You can specify the command using the -c option:

sk -i -c 'ag --color "{}"'

In the above example, the replace string {} will be replaced with the query you type before invoking the command. Use -I <replstr> to change replstr if you want.

For example, with the input “hello” in interactive mode, skim will replace the above command with ag --color "hello" and invoke it.

If you want to further narrow down the result returned by the command, press Ctrl-Q to toggle interactive mode.

  Preview Window

This is a great feature of fzf that skim borrows. For example, we use `ag' to find the matched lines, once we narrow down to the target lines, we want to finally decide which lines to pick by checking the context around the line. grep and ag has an option --context, skim can do better with preview window. For example:

    sk --ansi -i -c 'ag --color "{}"' --preview "preview.sh {}"

(Note the preview.sh (https://github.com/junegunn/fzf.vim/blob/master/bin/preview.sh) is a script to print the context given filename:lines:columns) You got things like this:

[IMAGE: preview demo (https://user-images.githubusercontent.com/1527040/30677573-0cee622e-9ebf-11e7-8316-c741324ecb3a.png)]

  How does it work?

If the preview command is given by the --preview option, skim will replace the {} with the current highlighted line surrounded by single quotes, call the command to get the output, and print the output on the preview window.

Sometimes you don’t need the whole line for invoking the command. In this case you can use {}, {1..}, {..3} or {1..5} to select the fields. The syntax is explained in the section “Fields Support”.

Last, you might want to configure the position of preview windows, use --preview-window. - --preview-window up:30% to put the window in the up position with height 30% of the total height of skim. - --preview-window left:10:wrap, to specify the wrap allows the preview window to wrap the output of the preview command. - --preview-window wrap:hidden to hide the preview window at startup, later it can be shown by the action toggle-preview.

  Fields support

Normally only plugin users need to understand this.

For example, you have the data source with the format:

    <filename>:<line number>:<column number>

However, you want to search <filename> only when typing in queries. That means when you type 21, you want to find a <filename> that contains 21, but not matching line number or column number.

You can use sk --delimiter ':' --nth 1 to achieve this.

Also you can use --with-nth to re-arrange the order of fields.

Range Syntax

•   <num> – to specify the num-th fields, starting with 1.

•   start.. – starting from the start-th fields, and the rest.

•   ..end – starting from the 0-th field, all the way to end-th field, including end.

•   start..end – starting from start-th field, all the way to end-th field, including end.

  Use as a library

Skim can now be used as a library in your Rust crates. The basic idea is to throw anything that is BufRead(we can easily turn a File for String into BufRead) and skim will do its job and bring us back the user selection including the selected items(with their indices), the query, etc.

First, add skim into your Cargo.toml:

    [dependencies]
    skim = "0.5.5"

Then try to run this simple example:

    extern crate skim;
    use skim::{Skim, SkimOptions};
    use std::default::Default;
    use std::io::Cursor;
    pub fn main() {
        let options: SkimOptions = SkimOptions::default().height("50%").multi(true);
        let input = "aaaaa\nbbbb\nccc".to_string();
        let selected_items = Skim::run_with(&options, Some(Box::new(Cursor::new(input))))
            .map(|out| out.selected_items)
            .unwrap_or_else(|| Vec::new());
        for item in selected_items.iter() {
            print!("{}: {}{}", item.get_index(), item.get_output_text(), "\n");
        }
    }

Check more examples under examples/ (https://github.com/lotabout/skim/tree/master/examples) directory.

FAQ

  How to ignore files?

Skim invokes find . to fetch a list of files for filtering. You can override that by setting the environment variable SKIM_DEFAULT_COMMAND. For example:

    $ SKIM_DEFAULT_COMMAND="fd --type f || git ls-tree -r --name-only HEAD || rg --files || find ."
    $ sk

You could put it in your .bashrc or .zshrc if you like it to be default.

  Some files are not shown in Vim plugin

If you use the Vim plugin and execute the :SK command, you might find some of your files not shown.

As described in #3 (https://github.com/lotabout/skim/issues/3), in the Vim plugin, SKIM_DEFAULT_COMMAND is set to the command by default:

    let $SKIM_DEFAULT_COMMAND = "git ls-tree -r --name-only HEAD || rg --files || ag -l -g \"\" || find ."

That means the files not recognized by git will not shown. Either override the default with let $SKIM_DEFAULT_COMMAND = '' or find the missing file by yourself.

Difference to fzf

fzf (https://github.com/junegunn/fzf) is a command-line fuzzy finder written in Go and skim (https://github.com/lotabout/skim) tries to implement a new one in Rust!

This project is written from scratch. Some decisions of implementation are different from fzf. For example:

1.  The fuzzy search algorithm is different.

2.  [STRIKEOUT:UI of showing matched items. fzf will show only the range matched while skim will show each character matched.] (fzf has this now)

3.  skim has an interactive mode.

4.  [STRIKEOUT:skim’s range syntax is git style]: now it is the same with fzf.

How to contribute

Create new issues (https://github.com/lotabout/skim/issues/new) if you meet any bugs or have any ideas. Pull requests are warmly welcomed.