[swift-evolution] Proposal Draft: Optional Upgrading Assignment.

Chris Lattner clattner at apple.com
Thu Feb 4 11:35:44 CST 2016

> On Feb 4, 2016, at 12:28 AM, Paul Ossenbruggen via swift-evolution <swift-evolution at swift.org> wrote:
> Draft Proposal feedback welcome.
> ## Introduction
> Currently to make a optional from a value the type name must be repeated:
> 	let x = “Some Value”
> 	let y : String? = x
> This takes away some of the advantage of type inference because the very next line I must specify the type.
> ## Proposal
> I propose the following syntax:
> 	let y? = x

This syntax already means something in Swift (though in this context it is illegal): "a?” is a pattern that binds to the inside of an optional.  It actually does the opposite of what you propose: it binds “a” to the thing inside an optional, which is the opposite of what you want.

As others have pointed out, using "Optional(x)” works today in an arbitrary expression position.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.swift.org/pipermail/swift-evolution/attachments/20160204/2442d67d/attachment.html>

More information about the swift-evolution mailing list