Add qr/\b{gcb}/

A function implements seeing if the space between any two characters is
a grapheme cluster break.  Afer I wrote this, I realized that an array
lookup might be a better implementation, but the deadline for v5.22 was
too close to change it.  I did see that my gcc optimized it down to
an array lookup.

This makes the implementation of \X go from being complicated to
trivial.

1 files changed, 1 insertions, 0 deletions

diff --git a/perl.h b/perl.h
index 9976f86bdd..b3b77ba121 100644
--- a/perl.h
+++ b/perl.h
@@ -2685,6 +2685,7 @@ typedef struct padname PADNAME;
 #endif
 
 #include "handy.h"
+#include "charclass_invlists.h"
 
 #if defined(USE_LARGE_FILES) && !defined(NO_64_BIT_RAWIO)
 #   if LSEEKSIZE == 8 && !defined(USE_64_BIT_RAWIO)