pub trait WeakTrue {
// Required method
fn weak_true(&self) -> bool;
// Provided methods
fn weak_false(&self) -> bool { ... }
fn weak_then<F, R>(&self, f: F) -> Option<R>
where F: FnOnce() -> R,
Self: Sized { ... }
fn weak_else<F, R>(&self, f: F) -> Option<R>
where F: FnOnce() -> R,
Self: Sized { ... }
}Expand description
Similar to the automatic implicit conversion to boolean values in weakly typed languages
| type | impl |
|---|---|
| float | self is not 0.0 / NaN |
| integer | self != 0 |
| reference / smart pointer | inner value impl |
| raw pointer | !self.is_null |
| Option | self.is_some |
| Result | self.is_ok |
| Poll | self.is_ready |
| str / slice / array | !self.is_empty |
| collections | !self.is_empty |
| unit | false |
| bool | self |
| fn / tuple / char | true |
Required Methods§
Sourcefn weak_true(&self) -> bool
fn weak_true(&self) -> bool
Similar to the automatic implicit conversion to boolean values in weakly typed languages
§Examples
assert!("c".weak_true());
assert!('c'.weak_true());
assert!('\0'.weak_true());
assert!([0].weak_true());
assert!((&0 as *const i32).weak_true());
assert!(Some(0).weak_true());
assert!(f64::NAN.weak_false());
assert!(0.0.weak_false());
assert!(0.weak_false());
assert!("".weak_false());
assert!([0; 0].weak_false());Refer to the documentation on WeakTrue
Provided Methods§
Sourcefn weak_false(&self) -> bool
fn weak_false(&self) -> bool
Default implementation is weak_true inversion
Sourcefn weak_then<F, R>(&self, f: F) -> Option<R>
fn weak_then<F, R>(&self, f: F) -> Option<R>
Run bool::then on WeakTrue::weak_true
§Examples
assert_eq!(1.weak_then(|| "a"), Some("a"));
assert_eq!(0.weak_then(|| "a"), None);Sourcefn weak_else<F, R>(&self, f: F) -> Option<R>
fn weak_else<F, R>(&self, f: F) -> Option<R>
Run bool::then on WeakTrue::weak_false
§Examples
assert_eq!(1.weak_else(|| "a"), None);
assert_eq!(0.weak_else(|| "a"), Some("a"));