# ClapCmd
A library to quickly build full-featured REPLs supported by CLAP and readline
(provided via rustyline)
## Features
- Full readline support that exposes all customization for rustyline
- emacs-style keyboard shortcuts
- command history
- Full integration with clap builders allowing for full-featured commands
- Tab completion for:
- commands and (TODO) command aliases
- arguments
- subcommands
- values supplied via `value_parsers` (i.e. a list of valid values)
- value hints (e.g. `ValueHint::FilePath`)
- TODO: callback and/or demo for how to query `value_parsers` at runtime
- Callback style approach with provided state
- Customizable prompts that can be updated at anytime during execution
- Support for writing to stdout outside of the command loop without mangling the input line via `get_async_writer()`
- Create loadable and unloadable command groups
## Basic Example
A minimal example showing a basic REPL is as follows:
```rust
use clapcmd::{ArgMatches, ClapCmd, ClapCmdResult, Command};
fn do_ping(_: &mut ClapCmd, _: ArgMatches) -> ClapCmdResult {
println!("pong");
Ok(())
}
fn main() {
let mut cmd = ClapCmd::default();
cmd.add_command(
do_ping,
Command::new("ping").about("do a ping")
);
cmd.run_loop();
}
```
## With State
To pass state or persistent information to callbacks, provide a `State` class like so.
The `State` class must implement `Clone` and `Default` traits, and can be accessed via
the `get_state()` and `set_state()` methods on the `ClapCmd` reference passed into the
callback.
```rust
use clapcmd::{ArgMatches, ClapCmd, ClapCmdResult, Command};
#[derive(Clone, Default)]
struct State {
counter: u32,
}
fn do_count(cmd: &mut ClapCmd<State>, _: ArgMatches) -> ClapCmdResult
where
State: Clone + Default,
{
let state = cmd.get_state();
let new_count = state.counter + 1;
println!("{}", new_count);
cmd.set_state(State { counter: new_count });
Ok(())
}
fn main() {
let mut cmd = ClapCmd::<State>::default();
cmd.add_command(
do_count,
Command::new("count").about("increment a counter")
);
cmd.run_loop();
}
```
## Other Examples
Refer to the [`examples/`](https://gitlab.com/clapcmd/clapcmd/-/tree/main/examples?ref_type=heads) folder for more demonstrations of advanced use cases
## MSRV
This library is tested with Rust 1.65 along with the latest version of Rust
## Related Projects
- reedline-repl-rs [https://github.com/arturh85/reedline-repl-rs](https://github.com/arturh85/reedline-repl-rs)