import Foundation
// WARNING: You included a flag that Swift doesn't support: J
// Wehn this flag is set, it allows duplicated capturing group names.
// By default, Swift captures only the last value matched for a repeated capture group.
// As an alternative, the pattern can be modified to contain one capturing group per group you want to get in the result.
let pattern = ##"""
^[ ]{0,3} # Leading space up to 3
(?<link_all>
(?<!\\)\[ # ID within brackets
(?!\^) # Make sure, this is not confused with a footnote
(?<link_id>.+?)
(?<!\\)\]
[ \t]* # Possibly with some space before colon
\:
[ \t]*\n?[ \t]* # Possibly with some space after the colon, possibly with a new line in between?
(?:
<(?<link_url>[^\>]+)> # link within <>
|
(?<link_url>\S+) # or link without <>
)
(?:
(?:
[ \t]+ # Either some space or tabs
|
[ \t]*\n[ \t]* # or a new line surrounded by 0 or more spaces or tabs
)
(?:
(?:
(?<link_title_container>['"]) # Title is surrounded ether by double or single quotes
(?<link_title>.+?)
\g{link_title_container} # make the sure enclosing mark balance
)
| # or
\((?<link_title>[^\)]+)\) # by parenthesis
)
)?
[ \t]* # Possibly ending with some trailing spaces or tab
)
(?:\n+|\Z) # terminated by a new line or end of file
"""##
let regex = try! NSRegularExpression(pattern: pattern, options: [.anchorsMatchLines, .allowCommentsAndWhitespace])
let testString = #"""
[1]: /url/ "Title"
[refid]: /path/to/something (Title)
[^block]:
Paragraph.
* List item
> Blockquote
Code block
"""#
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