peekay

If you’re programming the iPhone, sooner or later you’ll need regular expressions (regex).  By default OS X includes the ICU, an open source Unicode library which has extensive regex capabilities.

The ICU APIs are in C/C++ however, not Objective-C.   Fear not, RegexKitLite to the rescue.   This small library has done all the hard work of adding regex methods to NSString.  RegexKitLite is small, thread-safe, and quite fast.  It simply links to ICU —  unlike its bigger brother, RegexKit, which must be compiled against PCRE.

RegexKitLite is also easy to use:

#import "RegexKitLite.h"
NSString * foo = @"some string to search on";
NSString * regex = @"^(.+?)\s";
NSLog(@"Match: %@", [foo stringByMatching:regex capture:1]);

Then just link with –licucore and that’s it!!

Note: In Xcode I simply added -licucore to the “Other Linker Flags” in my project’s build configuration.  Maybe there’s a “better” way of doing this but this method works for me.