utf8.h, utfebcdic.h: Add #define

for future use

1 files changed, 9 insertions, 0 deletions

diff --git a/utfebcdic.h b/utfebcdic.h
index 3a4fcc28af..10b666afe2 100644
--- a/utfebcdic.h
+++ b/utfebcdic.h
@@ -205,8 +205,17 @@ above what a 64 bit word can hold */
  * definitions. */
 
 #define UTF8_IS_START(c)		_generic_isCC(c, _CC_UTF8_IS_START)
+
+#define UTF_IS_CONTINUATION_MASK    0xE0
+
 #define UTF8_IS_CONTINUATION(c)		_generic_isCC(c, _CC_UTF8_IS_CONTINUATION)
 
+/* The above instead could be written as this:
+#define UTF8_IS_CONTINUATION(c)                                                 \
+            (((NATIVE_UTF8_TO_I8(c) & UTF_IS_CONTINUATION_MASK)                 \
+                                                == UTF_CONTINUATION_MARK)
+ */
+
 /* Equivalent to ! UVCHR_IS_INVARIANT(c) */
 #define UTF8_IS_CONTINUED(c) 		cBOOL(FITS_IN_8_BITS(c)                 \
    && ! (PL_charclass[(U8) (c)] & (_CC_mask(_CC_ASCII) | _CC_mask(_CC_CNTRL))))