warrant

A macro like guard in Swift.

It helps to better express code logic without mind twists when checking conditions.

It implements what I termed "procedural warranty".

Usages

Add warrant = "0.2.0" to your Cargo.toml.

Before

// if some condition is not satisfied, early return.
let condition = is_satisfied();
if !condition {
    return;
}
// proceed

After

use warrant::warrant;
let condition = is_satisfied();
warrant!(condition, else {
    return;
});
// proceed

warrant 0.2 also supports let chains if you use Rust Edition 2024 and Rust >= 1.88.0.

warrant::warrant is also aliased as warrant::guard if you come from Swift and prefer guard.

License

MIT

Additional References

• Pattern Matched Guard: consider just use if-let-else
• "Structural Warranty": to enforce a condition on a struct, nutype is a good one.