Remember when typing felt good?

摘要

The third weirdness is that replacement templates use $ 1 for groups, rather than the usual 1. This isn't without precedent, but is nonetheless unusual among regular expression implementations. It isn't without explanation, either: Apple is following the ICU specification here (and quite possibly using ICU's implementation internally). The fourth weirdness is just how Cocoa-native this API is. The methods' names are verbose. The matching methods all require options and a range. All of the regex machinery is encapsulated in NSRegularExpression rather than being grafted onto the string class (aforementioned search option aside). And, as I already mentioned, it reuses for match objects a result class that was created for the spelling checker.