Why is result of filter with count not usable directly as conditional in Swift 3 [duplicate]

Answer 1

Swift has trouble parsing anonymous closure in the context of an if logical expression. You can work around this issue by parenthesizing the count expression:

if (myStructArray.filter{$0.isLocked == true}.count) < 4 {
// ^                                               ^
    print("Fewer than 4 locked")
}

or

if (myStructArray.filter{$0.isLocked == true}.count < 4) {
// ^                                                   ^
    print("Fewer than 4 locked")
}

or

if myStructArray.filter({$0.isLocked == true}).count < 4 {
//                     ^                     ^
    print("Fewer than 4 locked")
}