import Foundation
let pattern = #"\B@(?!.*(-){2,}.*)[a-z0-9](?:[a-z0-9-]{0,37}[a-z0-9])?\b"#
let regex = try! NSRegularExpression(pattern: pattern, options: .caseInsensitive)
let testString = #"""
@username
@user in a @user2 pagagraph of @user: text @usern-ame! @inalid-
@d
@12345678912345678912345678911112345678904
@invalid--username
and @valid-username-: l
@-invalid
@1
@a
@invalid-
hdj @hfd.com
some @valid-dd username
email@test.com
@validu-sername
@johndoe.
"""#
let stringRange = NSRange(location: 0, length: testString.utf16.count)
let matches = regex.matches(in: testString, range: stringRange)
var result: [[String]] = []
for match in matches {
var groups: [String] = []
for rangeIndex in 1 ..< match.numberOfRanges {
let nsRange = match.range(at: rangeIndex)
guard !NSEqualRanges(nsRange, NSMakeRange(NSNotFound, 0)) else { continue }
let string = (testString as NSString).substring(with: nsRange)
groups.append(string)
}
if !groups.isEmpty {
result.append(groups)
}
}
print(result)
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Swift 5.2, please visit: https://developer.apple.com/documentation/foundation/nsregularexpression