A minimal argument parser, with support for no-std and no-alloc
It mostly supports cmdlines in the form of program -foo value -bar value.
That means:
The last parameter can also be just a key without a value.
(This can be useful for -help.)
Add this to your Cargo.toml:
toml
[dependencies]
miniarg = "0.3"
The feature std is enabled by default and alloc and derive are optional.
A minimal example looks like this:
rust
let cmdline = "executable -key value";
let mut args = miniarg::parse(&cmdline, &["key"]);
assert_eq!(args.next(), Some(Ok((&"key", "value"))));
assert_eq!(args.next(), None);
If you don't want to pass a cmdline, you can use an iterator instead:
rust
let iter = vec!["executable", "-key", "value"].into_iter();
let mut args = miniarg::parse_from_iter(iter, &["key"]);
assert_eq!(args.next(), Some(Ok((&"key", "value"))));
assert_eq!(args.next(), None);
You can use collect::<Result<Vec<_>, _>>() to get a Vec:
rust
let cmdline = "executable -key value";
let args = miniarg::parse(&cmdline, &["key"]).collect::<Result<Vec<_>, _>>()?;
assert_eq!(args, vec![(&"key", "value")]);
If you compile with std or alloc, it also supports passing [ToString] instead of strings,
for example your own enum:
```rust
enum MyKeys {
Foo,
Bar,
}
impl std::fmt::Display for MyKeys {
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
std::fmt::Debug::fmt(self, f)
}
}
let cmdline = "executable -foo value -bar value";
let args = miniarg::parse(&cmdline, &[MyKeys::Foo, MyKeys::Bar])
.collect::
If you compile with derive, you can use a custom derive instead:
```rust
enum MyKeys {
Foo,
Bar,
}
let cmdline = "executable -foo value -bar value";
let args = MyKeys::parse(&cmdline).collect::
In this case a help text is generated from the documentation comments on your enum kinds,
help_text() retrieves it.
The code never panics, but the returned iterator will contain [ParseError]s
if anything goes wrong.
You might also want to take a look at the [split_args] module for lower level access.
License: MPL-2.0