how to compare value in swift optional

Question

var someString: String? = "a"    
someString = "b" 
// or someString = nil

Condition: someString is not nil and "a"

Example:

if someString != nil && someString != "a" {

}

Is it possible to condition a single?

Answer 1

The correct way in Swift 3 is to use a multi-clause condition:

if let bString = someString, bString != "a" {
    print("bString: '\(bString)' is not nil and is different from 'a'")
}

https://github.com/apple/swift-evolution/blob/master/proposals/0099-conditionclauses.md