vishalsodani / tealdeer

A very fast implementation of tldr in Rust.

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!

Docs (Installing, Usage, Configuration)

User documentation is available at https://dbrgn.github.io/tealdeer/!

The docs are generated using mdbook. They can be edited through the markdown files in the docs/src/ directory.

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.

Development

Creating a 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

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"!