1 unstable release
0.1.0 | Nov 21, 2021 |
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#1612 in Rust patterns
Used in decurse
7KB
102 lines
PFn
Provide fn_trait
's
call
,
call_mut
, and
call_once
on Stable Rust for functions / closures with ≤ 12 arguments.
Examples
Basic usage
let closure = |x: i32, y: i32, z: String| {
println!("{}", z);
x + y
};
// Once the `fn_trait` feature has stabilized, you would do this.
let result = closure.call((5, 42, "Hello World"));
// For now, use PFn.
let result = closure.pfn_call((5, 42, "Hello World"));
Generalizing over functions with different number of arguments
// Here, Func can be a function or closure that takes any number of arguments (actually 1 - 12 arguments).
struct Runnable<Args, Func: PFnOnce<Args>> {
func: Func,
args: Args
}
impl<Args, Func: PFnOnce<Args>> Runnable<Args, Func> {
fn run(self) -> Func::PFnOutput {
(self.func).pfn_call_once(self.args)
}
}
let runnable = Runnable {
func: |mut x: String| {
x.push_str("!!!");
x
},
args: ("hello world".into(),)
};
assert_eq!(runnable.run(), "hello world!!!");