Given the function
func mightReturnInt() throws -> Any {
return 3
}
combining `try?` and `as?` has a somewhat unexpected result:
if let int = try? mightReturnInt() as? Int {
print(int) // => Optional(3)
}
You’d need to add parentheses to end up with a non-optional:
if let int = (try? mightReturnInt()) as? Int {
print(int) // => 3
}
Apparently, `try?`’s precedence is lower than `as?`’s precedence. Should this
be changed?
On a similar note:
func mightReturnInt() throws -> Int? {
return 3
}
if let int = try? mightReturnInt() {
print(int) // => Optional(3)
}
Here, `try?` acts as a map, not as a flatMap, resulting in a double optional
(and in a single optional after unwrapping it). None of the possible
workarounds are particularly pretty:
if let temp = try? mightReturnInt(), let int = temp {
print(int) // => 3
}
or:
if let int = (try? mightReturnInt()) ?? nil {
print(int) // => 3
}
Once again, is this behaviour expected and desired, or should it be changed
while it still can?_______________________________________________
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