@swift-5.9.2
import RegexBuilder let regex = Regex { NegativeLookahead { Regex { Optionally(Anchor.wordBoundary.inverted) ":" ZeroOrMore(CharacterClass.anyOf(":").inverted) } } "_" NegativeLookahead { Regex { ZeroOrMore(CharacterClass.anyOf(":").inverted) ":" Optionally(Anchor.wordBoundary.inverted) } } } let txt = "\u{200C}:c_huzer01:" _ = txt.matches(of: regex)
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