import Foundation
let pattern = ##"""
^
(?:
[+-]? # optional sign
(?: # start a conditional group
\d+ # either a nonzero number of digits
| # or a decimal phrase
\d* # optional digits preceding the decimal
\.(?=\d) # a literal decimal followed by at least one digit
\d* # optionally some more digits
) # note this group is mandatory!
(?: # start an optional scientific notation group
[eE] # the scientific notation character
[+-]? # optional sign
\d+ # after sci notation, you cannot go directly to a decimal
)?
)
$
"""##
let regex = try! NSRegularExpression(pattern: pattern, options: [.anchorsMatchLines, .allowCommentsAndWhitespace])
let testString = #"""
67
-4
91.32
.67
-0.1123
4e5
71e-43
-323.456e-4.5
e
54e34e2
543.
43.e23
--323
e655
54e.3
-43e
"""#
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