8 releases
0.1.2 | Dec 20, 2023 |
---|---|
0.1.1 | Dec 20, 2023 |
0.1.0 | Dec 21, 2022 |
0.0.5 | Dec 18, 2022 |
0.0.1 | Nov 15, 2021 |
#433 in Rust patterns
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copstr: COPy STRing module using const generic for capacity
copstr::Str
wraps a fixed-size array of u8
and provides a
string-like interface on top. The size is specified using a const
generic argument.
The internal u8
array corresponds to UTF-8 encoded chars
. All
functions guarantee that the contents are valid UTF-8 and return
an error if they are not. Truncation only happens at UTF-8
boundaries.
copstr
is very useful when we want to add a string-like field
to a struct that implements Copy
but we don't want to give up
this trait.
Example usage
use copstr;
use std::convert::TryFrom;
// Create an owned fixed-size string with size 6 *on the stack*:
let mut string = copstr::Str::<6>::try_from("string")?;
// Use it as a regular string:
println!("contents: {}", string);
// Replace the contents with another string that fits the size 6:
string.replace("str")?;
// Append a letter:
string.push('i')?;
// Instead of returning a potential error, we can instead use
// truncating methods:
string.replace_trunc("stringification");
assert_eq!(string.as_str(), "string");
// `copstr::Str` implements Deref<Target=str>, so all `str`
// methods are available:
let split = format!("{:?}", string.split_at(3));
assert_eq!(split, r#"("str", "ing")"#);
// We can add a `copstr` to a struct without having to give up the
// `Copy` trait:
#[derive(Clone, Copy)]
pub struct Mystruct {
// ...
comment: copstr::Str<10>,
}
// We can (and should) create a type alias:
type MyStr = copstr::Str::<4>;
// We can create `copstr` in const contexts:
const TEST: MyStr = MyStr::new_const("TEST");
When using a const context, strings that don't fit generate a compilation error. For instance, the following doesn't compile:
const TEST_BAD: copstr::Str<3> = copstr::Str::<3>::new_const("TEST");