# easy-args
A Rust library for simple and lightweight command-line argument parsing, with:
- Easy to use declarative usage via [`ArgSpec`](https://docs.rs/easy-args/0.3.0/easy_args/struct.ArgSpec.html),
- Zero dependencies with other crates,
It's also worth pointing out what `easy-args` *is not*:
- Extensive. Only supports boolean flags, signed and unsigned 64-bit integers
and strings and array versions of those types.
- Fast. By no means is it super slow but it hasn't been made with maximum
performance in mind.
Documentation:
- [API reference (docs.rs)](https://docs.rs/easy-args)
## Usage
Add this to your `Cargo.toml`:
```toml
[dependencies]
easy-args = "0.3.0"
```
To get started using easy-args.
First you must define an `ArgSpec` which will determine what the command-line
arguments are for your program and will be used by the parser to do some
simple checks.
You make an `ArgSpec` with the builder pattern.
```
let spec = ArgSpec::build()
.boolean("fullscreen")
.uinteger_array(2, "size")
.done()?;
```
There is an `arg_spec!` macro which provides a nicer syntax.
```
let spec = arg_spec! {
fullscreen: bool,
size: [u64; 2],
};
```
Second you call `ArgSpecs`'s `parse()` method to retrieve the command-line
arguments in a processed form.
```
let args = spec.parse()?;
if args.boolean("fullscreen") == Some(&true) {
// Put application into fullscreen
}
```
And that's it! The arguments have been parsed and processed and can be
accessed via `Args`'s getter methods.
`ArgSpecBuilder` also has a `parse()` method so you don't have to make a
throwaway variable.
```
let args = ArgSpec::build()
.boolean("fullscreen")
.uinteger_array(2, "size")
.parse()
.unwrap();
```
## Versions
easy-args is an immature crate and as such may make breaking changes in future
versions.
Current easy-args versions are:
- Version 0.1.0 was released in June 2021, with the very first implementation.
- Version 0.1.1 was released a few hours afterwards to add documentation.
- Version 0.2.0 was released in June 2021, introduced array types, renamed
`unsigned_integer` methods to `uinteger` and added error checking for
to building `ArgSpec`'s.
- Version 0.3.0 was released in June 2021. Reorganised crate into single module to
simplify imports. Added features include:
- `arg_spec!` macro to provide a nicer syntax for `ArgSpec` building.
- `f64` and `[f64]` arguments now supported.
# License
easy-args is distributed under the terms of the MIT license.