On: Rust 1.50

[trevor-e]

Can you also please explain what the "||" is doing? That looks really weird to me coming from Swift and don't see it in the docs.

edit: thanks all, should have known it was a lambda :D, in Swift we can omit this. My first thought seeing "||" was some type of OR logic since it's in the context of if/else

[Sharlin → trevor-e]

Rust lambdas look like this:

    |ar,gs| expr

So `|| expr` is just a lambda function that takes no arguments and evaluates to `expr`.

[varajelle → trevor-e]

It is a lambda function with no parameters.

The argument of then() is a function which is evaluated only if the bool is true.

[laszlokorte → trevor-e]

empty parameter list of a closure.

rust: |x| x+x

swift: {x in x+x}

rust: || 42

swift: { 42 }