1 unstable release
Uses old Rust 2015
0.1.2 | Jun 28, 2017 |
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#1765 in Math
7KB
61 lines
Trinary — Rust types for trinary logic
Based on TriState code base.
A three-valued type equivalent to Option<bool>
:
enum TriState {
Yes,
No,
Unknown
}
A nice way to use this type is with a domain-specific type alias via pub use
.
(For esoteric reasons, a
simple typedef-style type alias doesn't work, though this Rust limitation will
eventually be removed.) For example, a spam classifier:
extern crate tristate;
pub use tristate::TriState as Spam;
trait Classify {
fn classify(&self) -> Spam;
}
impl Classify for Message { /* ... */ }
// ...
match message.classify() {
Spam::Yes => /* ... */,
Spam::No => /* ... */,
Spam::Unknown => /* ... */
}