Raku is full of surprises. Sometimes I read something what that me like “oh, really?”. Sometimes I realize than a fact evident for me is not so obvious for others.

Here is one of the kind.

Do you know that labels in Raku are objects? Take this:

FOO: for ^1 { .say }

FOO: is not a syntax construct to place an anchor in code but a way to create a Label instance:

FOO: dd FOO;
BAR: say BAR;

Due to its special and even specific nature class Label doesn’t provide much of an API. And what is available are methods to interact with loops. These are:

  • next
  • redo
  • last

Feels somewhat familiar, isn’t?

FOO: for ^10 {
    .say;
    FOO.last;
}

In a way we can say that last FOO is an indirect method invocation, even though it’s not really true as long as the core defines a multi-dispatch routine last, alongside with redo and next subs. But the corresponding routine candidates for labels actually do nothing but call Label’s methods.

Once again, objects are just about everywhere in Raku.

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