Caterpillar

I've been doing a bit of light reading on other languages. Just snooping through documentation and code samples. That inspired me to make a change to Caterpillar's syntax.

Here's how function literals looked like, as of yesterday:

{
    |a 0|
        a

    |a b|
        a b +
}

The parameters of each branch were delimited by |. This was directly inspired by Rust (which might have gotten it from Ruby).

As of last night, the same code looks like this:

{
    \ a 0 ->
        a

    \ a b ->
        a b +
}

Each branch now starts with a \, while a -> introduces the branch body. This is directly inspired by Roc, but I've also seen it in Elm and Futhark. I guess it's an ML-family thing.

I never quite liked how the same token was used on both ends of the parameter list. Now the start of that and the start of the body each look unique.