This crate provides a thin wrapper for [u8; N] to handle a stack-allocated byte array as a
fixed-length, String-like type through common traits such as Display, PartialEq, and
Deref<Target = str>.
```rust use fstr::FStr;
let x = FStr::tryfrom(b"foo")?; println!("{x}"); // "foo" asserteq!(x, "foo"); asserteq!(&x[..], "foo"); asserteq!(&x as &str, "foo"); assert!(!x.isempty()); assert!(x.isascii());
let mut y = FStr::tryfrom(b"bar")?; asserteq!(y, "bar"); y.makeasciiuppercase(); assert_eq!(y, "BAR");
const K: FStr<8> = FStr::fromstrunwrap("constant"); assert_eq!(K, "constant"); ```
Unlike String and [arrayvec::ArrayString], this type has the same binary representation
as the underlying [u8; N] and manages fixed-length strings only. The type parameter takes the
exact length (in bytes) of a concrete type, and the concrete type only holds the string values
of that size.
rust
let s = "Lorem Ipsum ✨";
assert_eq!(s.len(), 15);
assert!(s.parse::<FStr<15>>().is_ok()); // just right
assert!(s.parse::<FStr<10>>().is_err()); // too small
assert!(s.parse::<FStr<20>>().is_err()); // too large
```rust let x: FStr<10> = FStr::fromstrunwrap("helloworld"); let y: FStr<12> = FStr::fromstrunwrap("helloworld ");
// This code does not compile because FStr of different lengths cannot mix.
if x != y {
unreachable!();
}
```
Variable-length string operations are partially supported by utilizing a C-style NUL-terminated buffer and some helper methods.
```rust let mut buffer = FStr::<20>::fromstrlossy("haste", b'\0'); assert_eq!(buffer, "haste\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0");
let cstr = buffer.slicetoterminator('\0'); asserteq!(c_str, "haste");
use core::fmt::Write as ; write!(buffer.writerat(cstr.len()), " makes waste")?; asserteq!(buffer.slicetoterminator('\0'), "haste makes waste"); ```
std (optional; enabled by default) enables the integration with std. Disable default
features to operate this crate under no_std environments.serde (optional) enables the serialization and deserialization of FStrthrough serde.Licensed under the Apache License, Version 2.0.