import Foundation
let pattern = #"(<\w+)(\s*[\w-]+="[^"]+")*(\s*data-toggle="[^"]+")(\s*[\w-]+="[^"]+")*(\s*>)"#
let regex = try! NSRegularExpression(pattern: pattern)
let testString = ##"""
<td class="sky" data-toggle="up" id="heaven" >
<td class="sky" data-toggle="up" id="heaven" >
<td class="sky" data-toggle="up" id="heaven" >
<td class="sky" data-toggle="up" id="heaven" >
<td class="sky" data-toggle="up" id="heaven" >
<td class="sky" data-toggle="up" id="heaven" >
<td class="sky" data-toggle="up" id="heaven" >
<td class="sky" data-toggle="up" id="heaven" >
<a href="#" data-toggle="modal" data-target="xxxx"></a>
<a href="#"data-target="#available-assistance" data-toggle="modal" data-modal="yeah"></a>
<a href="#"data-target="#available-assistance" data-toggle="modal" data-modal="yeah"></a>
"""##
let stringRange = NSRange(location: 0, length: testString.utf16.count)
let substitutionString = #"$1$3$5"#
let result = regex.stringByReplacingMatches(in: testString, range: stringRange, withTemplate: substitutionString)
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