-#define BOL 2 /* 0x02 Match "" at beginning of line. */
-#define MBOL 3 /* 0x03 Same, assuming multiline. */
-#define SBOL 4 /* 0x04 Same, assuming singleline. */
-#define EOS 5 /* 0x05 Match "" at end of string. */
-#define EOL 6 /* 0x06 Match "" at end of line. */
-#define MEOL 7 /* 0x07 Same, assuming multiline. */
-#define SEOL 8 /* 0x08 Same, assuming singleline. */
-#define BOUND 9 /* 0x09 Match "" at any word boundary using native charset semantics for non-utf8 */
-#define BOUNDL 10 /* 0x0a Match "" at any locale word boundary */
-#define BOUNDU 11 /* 0x0b Match "" at any word boundary using Unicode semantics */
-#define BOUNDA 12 /* 0x0c Match "" at any word boundary using ASCII semantics */
-#define NBOUND 13 /* 0x0d Match "" at any word non-boundary using native charset semantics for non-utf8 */
-#define NBOUNDL 14 /* 0x0e Match "" at any locale word non-boundary */
-#define NBOUNDU 15 /* 0x0f Match "" at any word non-boundary using Unicode semantics */
-#define NBOUNDA 16 /* 0x10 Match "" at any word non-boundary using ASCII semantics */
-#define GPOS 17 /* 0x11 Matches where last m//g left off. */
-#define REG_ANY 18 /* 0x12 Match any one character (except newline). */
-#define SANY 19 /* 0x13 Match any one character. */
-#define CANY 20 /* 0x14 Match any one byte. */
-#define ANYOF 21 /* 0x15 Match character in (or not in) this class, single char match only */
-#define POSIXD 22 /* 0x16 Some [[:class:]] under /d; the FLAGS field gives which one */
-#define POSIXL 23 /* 0x17 Some [[:class:]] under /l; the FLAGS field gives which one */
-#define POSIXU 24 /* 0x18 Some [[:class:]] under /u; the FLAGS field gives which one */
-#define POSIXA 25 /* 0x19 Some [[:class:]] under /a; the FLAGS field gives which one */
-#define NPOSIXD 26 /* 0x1a complement of POSIXD, [[:^class:]] */
-#define NPOSIXL 27 /* 0x1b complement of POSIXL, [[:^class:]] */
-#define NPOSIXU 28 /* 0x1c complement of POSIXU, [[:^class:]] */
-#define NPOSIXA 29 /* 0x1d complement of POSIXA, [[:^class:]] */
-#define CLUMP 30 /* 0x1e Match any extended grapheme cluster sequence */
-#define BRANCH 31 /* 0x1f Match this alternative, or the next... */
-#define BACK 32 /* 0x20 Match "", "next" ptr points backward. */
-#define EXACT 33 /* 0x21 Match this string (preceded by length). */
-#define EXACTF 34 /* 0x22 Match this non-UTF-8 string (not guaranteed to be folded) using /id rules (w/len). */
-#define EXACTFL 35 /* 0x23 Match this string (not guaranteed to be folded) using /il rules (w/len). */
-#define EXACTFU 36 /* 0x24 Match this string (folded iff in UTF-8, length in folding doesn't change if not in UTF-8) using /iu rules (w/len). */
-#define EXACTFA 37 /* 0x25 Match this string (not guaranteed to be folded) using /iaa rules (w/len). */
-#define EXACTFU_SS 38 /* 0x26 Match this string (folded iff in UTF-8, length in folding may change even if not in UTF-8) using /iu rules (w/len). */
+#define SBOL 2 /* 0x02 Match "" at beginning of line: /^/, /\A/ */
+#define BOL 2 /* 0x02 type alias */
+#define MBOL 3 /* 0x03 Same, assuming multiline: /^/m */
+#define SEOL 4 /* 0x04 Match "" at end of line: /$/ */
+#define EOL 4 /* 0x04 type alias */
+#define MEOL 5 /* 0x05 Same, assuming multiline: /$/m */
+#define EOS 6 /* 0x06 Match "" at end of string: /\z/ */
+#define GPOS 7 /* 0x07 Matches where last m//g left off. */
+#define BOUND 8 /* 0x08 Match "" at any word boundary using native charset rules for non-utf8 */
+#define BOUNDL 9 /* 0x09 Match "" at any locale word boundary */
+#define BOUNDU 10 /* 0x0a Match "" at any word boundary using Unicode rules */
+#define BOUNDA 11 /* 0x0b Match "" at any word boundary using ASCII rules */
+#define NBOUND 12 /* 0x0c Match "" at any word non-boundary using native charset rules for non-utf8 */
+#define NBOUNDL 13 /* 0x0d Match "" at any locale word non-boundary */
+#define NBOUNDU 14 /* 0x0e Match "" at any word non-boundary using Unicode rules */
+#define NBOUNDA 15 /* 0x0f Match "" at any word non-boundary using ASCII rules */
+#define REG_ANY 16 /* 0x10 Match any one character (except newline). */
+#define SANY 17 /* 0x11 Match any one character. */
+#define CANY 18 /* 0x12 Match any one byte. */
+#define ANYOF 19 /* 0x13 Match character in (or not in) this class, single char match only */
+#define ANYOFL 20 /* 0x14 Like ANYOF, but /l is in effect */
+#define POSIXD 21 /* 0x15 Some [[:class:]] under /d; the FLAGS field gives which one */
+#define POSIXL 22 /* 0x16 Some [[:class:]] under /l; the FLAGS field gives which one */
+#define POSIXU 23 /* 0x17 Some [[:class:]] under /u; the FLAGS field gives which one */
+#define POSIXA 24 /* 0x18 Some [[:class:]] under /a; the FLAGS field gives which one */
+#define NPOSIXD 25 /* 0x19 complement of POSIXD, [[:^class:]] */
+#define NPOSIXL 26 /* 0x1a complement of POSIXL, [[:^class:]] */
+#define NPOSIXU 27 /* 0x1b complement of POSIXU, [[:^class:]] */
+#define NPOSIXA 28 /* 0x1c complement of POSIXA, [[:^class:]] */
+#define CLUMP 29 /* 0x1d Match any extended grapheme cluster sequence */
+#define BRANCH 30 /* 0x1e Match this alternative, or the next... */
+#define EXACT 31 /* 0x1f Match this string (preceded by length). */
+#define EXACTL 32 /* 0x20 Like EXACT, but /l is in effect. */
+#define EXACTF 33 /* 0x21 Match this non-UTF-8 string (not guaranteed to be folded) using /id rules (w/len). */
+#define EXACTFL 34 /* 0x22 Match this string (not guaranteed to be folded) using /il rules (w/len). */
+#define EXACTFU 35 /* 0x23 Match this string (folded iff in UTF-8, length in folding doesn't change if not in UTF-8) using /iu rules (w/len). */
+#define EXACTFA 36 /* 0x24 Match this string (not guaranteed to be folded) using /iaa rules (w/len). */
+#define EXACTFU_SS 37 /* 0x25 Match this string (folded iff in UTF-8, length in folding may change even if not in UTF-8) using /iu rules (w/len). */
+#define EXACTFLU8 38 /* 0x26 Rare cirucmstances: like EXACTFU, but is under /l, UTF-8, folded, and everything in it is above 255. */