Allow string concatenation when defining const values

[george-grec]

This is currently not valid syntax:

pub const foo = "foo"
pub const foo_bar = foo <> "bar"

It would be great if this would work!

[slightlybelowzen]

Just wondering why this isn't allowed? Is there a reason (since it seems fairly reasonable) or was it just left to be implemented later?

[lpil]

Thank you! Good suggestion.

@slightlybelowzen It's just something no one has implemented. The stuff that people decide to work on is the stuff that gets done.

[slightlybelowzen]

Fair enough, I could try to hack something together this weekend, see if I get anywhere😀

[lpil]

Wonderful! Thank you

[DeviousStoat]

I started looking into that. Not sure if @slightlybelowzen has started something too but it doesn't matter too much to me if my code doesn't go anywhere, this is a pretty cool task to start getting familiar with the code. I just had a question @lpil, do we want to support any binary operation in const statements or just the string concatenation? If foo <> "bar" is allowed shouldn't any operation on consts be allowed too?

pub const foo = 5
pub const foo_bar = foo + 5

[lpil]

Just concatenation for now as it does not require compile time code execution to implement.

[DeviousStoat]

why doesn't concatenation require compile time code execution? we should inline the concatenation operation? If so then what's the difference with inlining other operations?

[lpil]

Because that's how Erlang works.

[DeviousStoat]

yeah I don't know I was more thinking about the javascript part. sorry about the questions, I was just trying to understand a bit more. I will try to make a PR anyway, we'll see

[lpil]

Thank you 💜