[swift-users] try? with a function that returns an optional
Jonathan Bailey
jon889 at me.com
Mon Jan 25 07:01:48 CST 2016
In the language guide on the apple website, https://developer.apple.com/library/ios/documentation/Swift/Conceptual/Swift_Programming_Language/ErrorHandling.html#//apple_ref/doc/uid/TP40014097-CH42-ID542
It says the following assignments to x and y are equivalent:
func someThrowingFunction() throws -> Int { ... }
let x = try? someThrowingFunction()
// x has type `Int?`
let y: Int?
do {
y = try someThrowingFunction()
} catch {
y = nil
}
However this isn’t the case if someThrowingFunction also returns an optional, say:
func someThrowingFunction() throws -> Int? { ... }
The type of x would be `Int??`, but the type of y is still `Int?`, is there some way to make the `try?` return an `Int?` instead of a double optional, which is not very helpful.
Thanks,
Jonathan
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.swift.org/pipermail/swift-users/attachments/20160125/dcee383d/attachment.html>
More information about the swift-users
mailing list