Enum magnus::block::Yield

pub enum Yield<I> {
    Iter(I),
    Enumerator(Enumerator),
}

Helper type for functions that either yield a single value to a block or return an Enumerator.

I must implement Iterator<Item = T>, where T implements Into<Value>.

Examples

use magnus::{block::{block_given, Yield}, Value};

fn count_to_3(rb_self: Value) -> Yield<impl Iterator<Item = u8>> {
    if block_given() {
        Yield::Iter((1..=3).into_iter())
    } else {
        Yield::Enumerator(rb_self.enumeratorize("count_to_3", ()))
    }
}

Could be called from Ruby like:

a = []
count_to_3 {|i| a << i}   #=> nil
a                         #=> [1,2,3]
enumerator = count_to_3
enumerator.next           #=> 1
enumerator.next           #=> 2

Variants

Iter(I)

Yields I::Item to given block.

Enumerator(Enumerator)

Returns Enumerator from the method.