tealdeer

Crate	CI (Linux/macOS/Windows)

A very fast implementation of tldr in Rust: Simplified, example based and community-driven man pages.

If you pronounce "tldr" in English, it sounds somewhat like "tealdeer". Hence the project name :)

In case you're in a hurry and just want to quickly try tealdeer, you can find static binaries on the GitHub releases page!

Goals

High level project goals:

• Download and cache pages
• Don't require a network connection for anything besides updating the cache
• Command line interface similar or equivalent to the NodeJS client
• Be fast

A tool like tldr should be as frictionless as possible to use. It should be easy to invoke (just tldr tar, not using another subcommand like tldr find tar) and it should show the output as fast as possible.

tealdeer reaches these goals. During a (highly non-scientific) test (see #38 for details), I tested the invocation speed of tldr <command> for a few of the existing clients:

Client	Times (ms)	Avg of 5 (ms)
Tealdeer	15/11/5/5/11	9.4 (100%)
C client	11/5/12/11/15	10.8 (115%)
Bash client	15/19/22/25/24	21.0 (223%)
Go client by k3mist	98/96/100/95/101	98.8 (1'051%)
Python client	152/148/151/158/140	149.8 (1'594%)
NodeJS client	169/171/170/170/170	170.0 (1'809%)

tealdeer was the winner here, although the C client and the Bash client are in the same speed class. Interpreted languages are clearly much slower to invoke, a delay of 170 milliseconds is definitely noticeable and increases friction for the user.

These are the clients I tried but failed to compile or run: Haskell client, Ruby client, Perl client, Go client by anoopengineer, PHP client.

Usage

tldr [options] <command>
tldr [options]

Options:

    -h --help            Show this screen
    -v --version         Show version information
    -l --list            List all commands in the cache
    -f --render <file>   Render a specific markdown file
    -o --os <type>       Override the operating system [linux, osx, sunos, windows]
    -u --update          Update the local cache
    -c --clear-cache     Clear the local cache
    -p --pager           Use a pager to page output
    -m --markdown        Display the raw markdown instead of rendering it
    -q --quiet           Suppress informational messages
    --config-path        Show config file path
    --seed-config        Create a basic config
    --color <when>       Control when to use color [always, auto, never] [default: auto]

Examples:

    $ tldr tar
    $ tldr --list

To control the cache:

    $ tldr --update
    $ tldr --clear-cache

To render a local file (for testing):

    $ tldr --render /path/to/file.md

Installing

Static Binaries (Linux)

Static binary builds (currently for Linux only) are available on the GitHub releases page. Simply download the binary for your platform and run it!

Builds for other platforms are planned.

Cargo Install (any platform)

Build and install the tool via cargo...

$ cargo install tealdeer

(Note: You might need to install OpenSSL development headers, otherwise you get a "failed to run custom build command for openssl-sys" error message. The package is called libssl-dev on Ubuntu.)

From Package Manager

tealdeer has been added to a few package managers:

• Arch Linux AUR: tealdeer, tealdeer-bin or tealdeer-git
• Fedora: tealdeer
• FreeBSD: sysutils/tealdeer
• macOS Homebrew: tealdeer
• NetBSD: sysutils/tealdeer
• Nix: tealdeer
• openSUSE: tealdeer
• Solus: tealdeer
• Void Linux: tealdeer

From Source (any platform)

tealdeer requires at least Rust 1.39.

Debug build with logging enabled:

$ cargo build --features logging

Release build without logging:

$ cargo build --release

To enable the log output, set the RUST_LOG env variable:

$ export RUST_LOG=tldr=debug

Configuration

The tldr command can be customized with a config file called config.toml. Creating the config file can be done manually or with the help of tldr:

$ tldr --seed-config

The configuration file path follows OS conventions. It can be queried with the following command:

$ tldr --config-path

The directory where the configuration file resides may be overwritten by the environment variable TEALDEER_CONFIG_DIR. Remember to use an absolute path. Variable expansion will not be performed on the path.

Style

Using the config file, the style (e.g. colors or underlines) can be customized.

Possible styles:

• description: The initial description text
• command_name: The command name as part of the example code
• example_text: The text that describes an example
• example_code: The example itself, except the command_name and example_variable
• example_variable: The variables in the example

Currently supported attributes:

• foreground (color string, see below)
• background (color string, see below)
• underline (true or false)
• bold (true or false)

The currently supported colors are:

• black
• red
• green
• yellow
• blue
• purple
• cyan
• white

Example customization:

Display

In the display section you can configure the output format.

use_pager

Specifies whether the pager should be used by default or not (default false).

[display]
use_pager = true

When enabled, less -R is used as pager. To override the pager command used, set the PAGER environment variable.

NOTE: This feature is not available on Windows.

compact

Set this to enforce more compact output, where empty lines are stripped out (default false).

[display]
compact = true

Automatic updates

tealdeer can refresh the cache automatically when it is outdated. This behavior can be configured in the updates section and is disabled by default.

auto_update

Specifies whether the auto-update feature should be enabled (defaults to false).

[updates]
auto_update = true

auto_update_interval_hours

Duration, since the last cache update, after which the cache will be refreshed (defaults to 720 hours). This parameter is ignored if auto_update is set to false.

[updates]
auto_update = true
auto_update_interval_hours = 24

Autocompletion

• Bash: copy bash_tealdeer to /usr/share/bash-completion/completions/tldr
• Fish: copy fish_tealdeer to ~/.config/fish/completions/tldr.fish
• Zsh: copy zsh_tealdeer to /usr/share/zsh/site-functions/_tldr

Development

To run tests:

$ cargo test

To run lints:

$ rustup component add clippy
$ cargo clean && cargo clippy

MSRV (Minimally Supported Rust Version)

Tealdeer will not bump the MSRV requirement in patch versions, but it may increase it in minor versions. The reason is that many important libraries (e.g. the Tokio ecosystem, which is a dependency of reqwest, which is used for downloading the cache) do not follow a static MSRV, but instead follow a "stable + last n releases" approach. Trying to guarantee the same MSRV across all minor releases would be a futile attempt.

License

Licensed under either of

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT) at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

Thanks to @SShrike for coming up with the name "tealdeer"!