???(_:_:)
public func ??? <T>(optional: T?, defaultValue: @autoclosure () -> String) -> String
Mechanica
Optional-string-coalescing operator.
The ??? operator takes any optional
on its left side and a default
string value on the right, returning a string.
If the optional value is non-nil, it unwraps it and returns its string description, otherwise it returns the default value.
-
Declaration
Swift
public func ??? <T>(optional: T?, defaultValue: @autoclosure () -> String) -> String