import Foundation
let pattern = #"^rgba?\((?:(?:(?:[0-9]{1,3} ){2}[0-9]{1,3}|(?:[0-9]{1,3}% ){2}[0-9]{1,3}%)(?: \/ (?:[0-9]{1,3}%|1|0|0?\.[0-9]+))?|(?:(?:[0-9]{1,3}, ){2}[0-9]{1,3}|(?:[0-9]{1,3}%, ){2}[0-9]{1,3}%)(?:, (?:[0-9]{1,3}%|1|0|0?\.[0-9]+))?)\)$"#
let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines)
let testString = #"""
// invalid
rgb()
rgba()
rgb(123)
rgb(11 22 )
rgb(11 22 2 / 03)
rgb(11 22 2 / 10)
rgb(1 2 3 / 0.34%)
rgb(11% 22 33)
rgb(111 222% 333)
rgb(1 22 333 )
rgb(1 2 3, 1)
rgb(1 2, 3 / 1)
// valid
rgb(111 22 333)
rgb(1 2 3)
rgb(11 22 33)
rgb(111 222 333)
rgb(1 22 333)
rgb(1 2 3 / 1)
rgb(11 22 2 / 0)
rgb(1 2 3 / 0.34)
rgb(1 2 3 / .34)
rgb(1 2 3 / 0.34)
rgb(1 2 3 / 1%)
rgb(1 2 3 / 10%)
rgb(1 2 3 / 100%)
rgb(11 22 2 / 0%)
rgb(1 2 3 / 34%)
rgb(1 2 3 / 4%)
rgb(111 22 333)
rgb(1% 2% 3%)
rgb(11% 22% 2% / 0)
rgb(12%, 0%, 100%)
rgb(111, 22, 333)
rgb(1, 2, 3)
rgb(1, 2, 3, 1)
"""#
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