cutlass

experimental auto-currying for rust functions

example

this currently works only on nightly with the type_alias_impl_trait feature enabled.

```rust

![feature(typealiasimpl_trait)]

[cutlass::curry]

fn add(x: u32, y: u32, z: u32) -> u32 { return x + y + z; }

fn main() { let plus3 = add(1)(2); let v: Vec = (1..=3).map(plus3).collect(); assert_eq!(v, vec![4, 5, 6]); } ```

how it works

the #[curry] proc-macro expands the above add function to something like this (roughly):

rust type T0 = u32; type T1 = impl Fn(u32) -> T0; type T2 = impl Fn(u32) -> T1; fn add(x: u32) -> T2 { return (move |y| move |z| x + y + z); }

gotchas

• doesn't yet work for method functions (signatures with self)
• the function has to have a return value
• works only on nightly with type_alias_impl_trait enabled

testing

test this crate with cargo +nightly test.

to view macro expansions, install cargo-expand and run cargo expand --test <test name>. expand tests/smoke.rs for example:

cargo expand --test smoke