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+# cutlass
+
+> experimental auto-currying for rust functions
+
+### example
+
+this currently works only on nightly with the
+`type_alias_impl_trait` feature enabled.
+
+```rust
+#![feature(type_alias_impl_trait)]
+
+#[cutlass::curry]
+fn add(x: u32, y: u32, z: u32) -> u32 {
+    return x + y + z;
+}
+
+fn main() {
+    let plus_3 = add(1)(2);
+    let v: Vec<u32> = (1..=3).map(plus_3).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
+```