Swift Use of unresolved operator '=~' - swift

Question

I'm trying to find a code for swift password strength checker, then I see this from github I fix some codes but there's a operator that I don't understand, it's =~
This is my code
enum PasswordStrength: Int {
case None
case Weak
case Moderate
case Strong
static func checkStrength(password: String) -> PasswordStrength {
var len: Int = password.count
var strength: Int = 0
switch len {
case 0:
return .None
case 1...4:
strength += 1
case 5...8:
strength += 2
default:
strength += 3
}
// Upper case, Lower case, Number & Symbols
let patterns = ["^(?=.*[A-Z]).*$", "^(?=.*[a-z]).*$", "^(?=.*[0-9]).*$", "^(?=.*[!##%&-_=:;\"'<>,`~\\*\\?\\+\\[\\]\\(\\)\\{\\}\\^\\$\\|\\\\\\.\\/]).*$"]
for pattern in patterns {
if (password =~ pattern).boolValue {
strength += 1
}
}
switch strength {
case 0:
return .None
case 1...3:
return .Weak
case 4...6:
return .Moderate
default:
return .Strong
}
}
}
and my error Use of unresolved operator '=~' was pointing at =~, what's the meaning of it and how can I resolve it?

Answer 1

=~ seems like a custom operator (or maybe the pattern matching operator ~= was different in previous Swift version, but I doubt that, since the pattern matching operator cannot handle regex matching or at least cannot handle it in Swift 5).
You can replace the =~ with if password.range(of: pattern, options: .regularExpression) != nil to check if a regular expression matches your password.
Also, enum cases should be lowerCamelCase
Full working code:
enum PasswordStrength: Int {
case none
case weak
case moderate
case strong
static func checkStrength(password: String) -> PasswordStrength {
let len = password.count
var strength: Int = 0
switch len {
case 0:
return .none
case 1...4:
strength += 1
case 5...8:
strength += 2
default:
strength += 3
}
// Upper case, Lower case, Number & Symbols
let patterns = ["^(?=.*[A-Z]).*$", "^(?=.*[a-z]).*$", "^(?=.*[0-9]).*$", "^(?=.*[!##%&-_=:;\"'<>,`~\\*\\?\\+\\[\\]\\(\\)\\{\\}\\^\\$\\|\\\\\\.\\/]).*$"]
for pattern in patterns {
if password.range(of: pattern, options: .regularExpression) != nil {
strength += 1
}
}
switch strength {
case 0:
return .none
case 1...3:
return .weak
case 4...6:
return .moderate
default:
return .strong
}
}
}
You can also simplify the for loop by using a where clause like this:
for pattern in patterns where password.range(of: pattern, options: .regularExpression) != nil {
strength += 1
}