Suppose you know PCRE, specifically NSRegularExpression. How to convert to Swift's Regex DSL?

First, you don't have to. With JavaScript modern /literals/, you can keep typing line noise. But if you're itchy to try the shiny, this table can get you going.

Tip: When exploring, look for types conforming to RegexComponent (scroll to the bottom).

� represents 'some regex', 'whatever', and 'etc.'

I want to match NSRegularExpression Swift Regex
Anchors
Word Boundary \b Anchor.wordBoundary
Start of Line ^ Anchor.startOfLine
End of Line $ Anchor.endOfLine
Characters
Any Character . CharacterClass.any
Newline \n CharacterClass.newlineSequence
Digit \d CharacterClass.digit
Word Character \w CharacterClass.word
Whitespace \s CharacterClass.whitespace
Character set [Helo] CharacterClass.anyOf
Lookaround
Positive Lookbehind (?<=Hello)World Not Available
Negative Lookbehind (?<!Hello)World Not Available
Positive Lookahead Hello(?=World) Lookahead { � }
Negative Lookahead Hello(?!World) NegativeLookahead { � }
Misc
Capture Group (World) Capture { � }
Non Capturing Group (?:World) Implicitly in trailing { � }
Explicitly with Regex
Backreference \1 Reference
Or �|� ChoiceOf { � }
Quantifiers
Optional �? Optionally { � }
╠ Lazy �?? Optionally(.reluctant) { � }
╚ Possessive �?+ Optionally(.possessive) { � }
Zero or More �* ZeroOrMore { � }
╠ Lazy �*? ZeroOrMore(.reluctant) { � }
╚ Possessive �*+ ZeroOrMore(.possessive) { � }
Once or More �+ OneOrMore { � }
╠ Lazy �+? OneOrMore(.reluctant) { � }
╚ Possessive �++ OneOrMore(.possessive) { � }
Exactly n times �{n} Repeat(count: n) { � }
At least n times �{n,} Repeat(n...) { � }
At most m times �{0,m} Repeat(...m) { � }
n to m times, inclusive �{n,m} Repeat(n...m) { � }