Better spec compliancy for rhemyn

rhemyn/README.md

@@ -8,33 +8,43 @@ Made for use with Porffor but could possibly be adapted, implementation/library
 - Wasm function returned expects an i32 pointer to a UTF-16 string (can add UTF-8 option later if someone else actually wants to use this)
 
 ## syntax
-🟢 supported 🟡 partial 🟠 parsed only 🔴 unsupported
+🟢 supported 🟡 partial 🟠 parsed only
 
 - 🟢 literal characters (eg `a`)
 - 🟢 escaping (eg `\.\n\cJ\x0a\u000a`)
   - 🟢 character itself (eg `\.`)
   - 🟢 escape sequences (eg `\n`)
   - 🟢 control character (eg `\cJ`)
-  - 🟢 unicode code points (eg `\x00`, `\u0000`)
+  - 🟢 unicode code points (eg `\x00`, `\u0000`, `\u{10FFFF}`)
 - 🟢 sets (eg `[ab]`)
   - 🟢 ranges (eg `[a-z]`)
   - 🟢 negated sets (eg `[^ab]`)
+  - 🟠 unicode set expressions (eg `[[a-z]&&[b-e]]`)
 - 🟢 metacharacters
   - 🟢 dot (eg `a.b`)
   - 🟢 digit, not digit (eg `\d\D`)
   - 🟢 word, not word (eg `\w\W`)
   - 🟢 whitespace, not whitespace (eg `\s\S`)
+  - 🟠 unicode properties (eg `\p{ID_Continue}`)
 - 🟡 quantifiers
   - 🟡 star (eg `a*`)
   - 🟡 plus (eg `a+`)
   - 🟡 optional (eg `a?`)
   - 🟠 lazy modifier (eg `a*?`)
-  - 🔴 n repetitions (eg `a{4}`)
-  - 🔴 n-m repetitions (eg `a{2,4}`)
+  - 🟠 n repetitions (eg `a{4}`)
+  - 🟠 n-m repetitions (eg `a{2,4}`)
+- 🟠 disjunctions (eg `a|b`)
 - 🟠 groups
-  - 🟠 capturing groups (`(a)`)
-  - 🔴 non-capturing groups (`(?:a)`)
-- 🔴 assertions
-  - 🔴 beginning (eg `^a`)
-  - 🔴 end (eg `a$`)
-  - 🔴 word boundary assertion (eg `\b\B`)
+  - 🟠 capturing groups (eg `(a)`)
+  - 🟠 named capturing groups (eg `(?<foo>a)`)
+  - 🟠 non-capturing groups (eg `(?:a)`)
+  - 🟠 backreferences (eg `\1`)
+  - 🟠 named backreferences (eg `\k<foo>`)
+- 🟠 assertions
+  - 🟠 beginning (eg `^a`)
+  - 🟠 end (eg `a$`)
+  - 🟠 word boundary assertion (eg `\b\B`)
+  - 🟠 positive look-ahead (eg `(?=a)`)
+  - 🟠 negative look-ahead (eg `(?!a)`)
+  - 🟠 positive look-behind (eg `(?<=a)`)
+  - 🟠 negative look-behind (eg `(?<!a)`)