ArrayExprSyntax initializer that takes an array of ExprSyntax

[grynspan]

Description

Constructing an ArrayExprSyntax from a Swift array of arbitrary ExprSyntax values is a bit of a pain. Right now, we do silly dances like:

let exprs: [ExprSyntax] = ...
let exprString = exprs.lazy
  .map(\.trimmedDescription)
  .joined(separator: ", ")
return ExprSyntax("[\(raw: exprString)]").as(ArrayExprSyntax.self)

Having a convenience initializer that inserts commas and necessary trailing trivia would make this much nicer.

[ahoppen]

Tracked in Apple’s issue tracker as rdar://109483386

[gibachan]

Is it okay for me to handle this issue?

[kimdv]

Hi @grynspan!

Would you be able to achieve your request with the result builder initialiser of ArrayExprSyntax

Maybe something like

return ArrayExprSyntax {
    for item in [1, 2, 3, 4] {
        ArrayElementSyntax(expression: ExprSyntax("\(raw: item)"))
    }  
}

[ahoppen]

Is it okay for me to handle this issue?

Sure, I assigned it to you.

Would you be able to achieve your request with the result builder initialiser of ArrayExprSyntax

Maybe something like

return ArrayExprSyntax {
    for item in [1, 2, 3, 4] {
        ArrayElementSyntax(expression: ExprSyntax("\(raw: item)"))
    }  
}

To speak on @grynspan’s behalf: The motivating example here is where you already have an [ExprSyntax]. You could do the following but that seems kind dumb

ArrayExprSyntax {
  for element in arrayElements {
    element
  }
}

[grynspan]

Would you be able to achieve your request with the result builder initialiser of ArrayExprSyntax

Yes! However it seems like a convenience initializer here is worth implementing, because "constructing an ArrayExprSyntax from an array of ExprSyntax" seems pretty useful. :)