1 unstable release
0.1.0 | Oct 20, 2023 |
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#2200 in Rust patterns
5KB
unwrap_let!
A Rust macro for quickly unwrapping a refutable pattern.
Install
Add unwrap_let
to your dependency by running cargo add unwrap_let
or editing Cargo.toml
:
[dependencies]
unwrap_let = "0.1.0"
Then, import unwrap_let
macro either by [macro_use]
or a use
statement.
// Option 1:
// Having this line in `lib.rs` or `main.rs` allows you to use `unwrap_let` in
// any file in your project without additional `use` statement.
#[macro_use]
extern crate unwrap_let;
// Option 2:
// Or, you can import it in each file that uses this macro.
use unwrap_let::unwrap_let;
Example
let val = Some(123);
unwrap_let!(Some(x) = val);
// `x` is defined
assert_eq!(x, 123);
enum Integer {
Signed(i64),
Unsigned(u64),
}
fn negate(unchecked_num: Integer) -> Integer {
unwrap_let!(Integer::Signed(num) = unchecked_num, "expected a signed integer");
Integer::Signed(-num)
}
Minimum Supported Rust Version
unwrap_let
internally uses "let-else" statement, which was introduced in Rust 1.65 (Nov 2022).
License
This project is licensed under the (MIT license)[./LICENSE].