import Foundation
let pattern = ##"""
(?(DEFINE)
(?<XHTML>
(?&comment)*\s*
(?&DOCTYPE)
(?&comment)*\s*
(?&HTML)
(?&comment)*\s*
)
# HTML element
(?<HTML>
<html(?&attrs)?>(?&content)<\/html>
)
# Match content
(?<content>
\s*
(?:
((?&tag) | [^<>]+)\s*
)*
)
# General tag
(?<tag>
<((?&tagname))(?&attrs)?\s*(?:
\/>|
>\s*(?&content)\s*
<\/\g'-1'>
)|(?&comment)
)
# Attributes
(?<attrs>\s+
# The name
(?&keyword) (
\s*=\s*
(?:
(?&keyword)|(?&string)
)
)?
(?&attrs)?
)
(?<string>
"(?:\\.|.)+?"|
'(?:\\.|.)+?'
)
(?<comment>
\s*<!--(.+?)-->\s*
)
# Match keyword
(?<keyword>[^\s\/>"'=]+)
# Match tag name
(?<tagname>(?!xml)[A-Za-z_][A-Za-z\d_.-]*)
# DOCTYPE expression
(?<DOCTYPE>
<!doctype\s+x?html\s*(public\s*(?&string))?(\s+(?&string))*>
)
)
^\s*(?&XHTML)\s*$
"""##
let regex = try! NSRegularExpression(pattern: pattern, options: [.caseInsensitive, .allowCommentsAndWhitespace, .dotMatchesLineSeparators])
let testString = #"""
<!-- test -->
<!DOCTYPE html
PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">
<html goat:style="''inva'lid css I know">textttt<head></head><body><div class="onfoodstamps"><div class="upper">foo<p>ayyy</p>bar</div>baz</div><br/></head></html>
"""#
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