import Foundation
let pattern = ##"""
(# the number at the beginning
[-+]? # optional leading sign
\d+# the digits to the left of the decimal
(?:\.\d+)? # an optional decimal amount
)
(#units
\/? #optional slash
[a-zA-Z]+ # must be alphabetic
(\^?[-+]?\d+(?:\.\d+)?)? # a caret followed by our same/initial digit pattern
)+
"""##
let regex = try! NSRegularExpression(pattern: pattern, options: [.anchorsMatchLines, .allowCommentsAndWhitespace])
let testString = #"""
Very much a stupid beginner question, but trying to make a regex expression which would take in "5ms-1", "17km/h" or "9ms^-2" etc. with these ambiguous units and ambiguous formats. Please help, I can't manage it
5ms-1
17km/h
9ms^-2
-5mph
6.8m/h
+8liters/hectacre^2
5/h
1m^2s^2
this will also match the 21st century, 7eleven, 3M, and similar things.
"""#
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