In a similar vein of "why this not that," I'm not ...

# getting-started

[Uberunix]

In a similar vein of "why this not that," I'm not finding a compelling explanation for the differentiated uses of = and ->. Specifically in the contexts of single expression functions vs. lambdas. They're both predicates to their respective return statements, and as far as I can see, serve the same purpose. So why the distinction in form? Why not just use arrow syntax in both cases?

[Youssef Shoaib [MOD]]

I guess the distinction between

var bar: Int
let {
  bar = 5
}
// vs
let {
  bar -> 5
}

matters.
Also, = for single expression functions has no {}, but lambdas always have {}

[Uberunix]

That's a fair point! My perspective is definitely limited. I'm thinking mostly of all the property extensions I'm writing in exercises right now. It feels arbitrary to right get() = instead of get() -> since the latter seems like a more idiomatic representation of "return".

[Joffrey]

But -> is not "return", it just separates the parameters from a lambda's body (which could contain many statements before the returned expression). In function declarations (both fun and get), there are parentheses for parameters, so you don't need an extra separator.

The = sign, on the other hand, always expects a single expression on the right-hand side - you can't have statements there. So it's about whether the body has `return`s or a single expression. Lambdas are neither of those (not necessarily a single expression, and no returns), so it makes sense to me that the syntax is different