Macro tuplez::mapper_once

macro_rules! mapper_once {
    ($($x:ident $(, $lt:lifetime)*: $it:ty $(=> $ot:ty)? : $e:expr);* $(;)?) => { ... };
    ($($x:ident $(, $lt:lifetime)*: $it:ty $(=> $ot:ty)? : $e:expr ;)*
        $(_ $(=> $ot2:ty)? : $f:ident $(where $($t:tt)*)?)?) => { ... };
    (@impl _ : $f:ident $(where $($t:tt)*)?) => { ... };
    (@impl _ => $ot:ty : $f:ident $(where $($t:tt)*)?) => { ... };
    (@impl $x:ident : $it:ty : $e:expr) => { ... };
    (@impl $x:ident $(, $lt:lifetime)* : $it:ty : $e:expr) => { ... };
    (@impl $x:ident : $it:ty => $ot:ty : $e:expr) => { ... };
    (@impl $x:ident $(, $lt:lifetime)* : $it:ty => $ot:ty : $e:expr) => { ... };
}

Provides a simple way to create a functor that implements MapperOnce.

Syntax

The syntax is exactly the same as mapper!. The difference is that mapper_once! take elements of the tuple instead of pass in their immutable references.

Example

use tuplez::*;

let tup = tuple!(vec![1, 2, 3], "hello".to_string());
let tup2 = tup.foreach_once(mapper_once!{
    x: Vec<i32> => Box<[i32]> : x.into();
    x: String : x
});
// assert_eq!(tup, ... ); // No, `tup` has been moved
assert_eq!(
    tup2,
    tuple!(
        Box::<[i32; 3]>::new([1, 2, 3]) as Box<[i32]>,
        "hello".to_string()
    )
);