# Fn

---

```text
Fn_class `alias Enum[.partial; .native; .process; .iterator; .closure; .bound; .regex]

Fn[Fn_class; RETURN_TYPE; ARGS; STATE; List]
```

## \`return

## Transient Union Return Chaining

# Iterating

## \`yield

Yielding wraps the value in the transient union `Next`

Return `Void` to stop iteration

```text
fn : Fn[n] $ ( @ 1 .. n { `yield 2 * x }[x] )
it : fn `call 10
// invoking
@ it { `log v }[v] // 2 4 6 8 10 12 14 16 18 20
// same as above
@ {
    # `call it {
        .value { `log v }[v]
        .done { `break }
    }
}
```

# Calling

## \`fork

```text
task : `fork fn
value : `wait task
```

## \`call

```text
fn `call args // `wait fn `task args
```