update opam, README

Author: zazedd

README.md

@@ -110,17 +110,13 @@ The patterns are plain strings of the form accepted by `Re.Pcre`, with the follo
     the whole pattern matches, and `string option` if the variable is bound
     to or nested below an optionally matched group.
 
-  - `(N?<var>)` gets substituted by the value of the globally defined string variable named `var`,
+  - `(?&var)` refers to any identifier bound to a typed regular expression of type `'a Re.t`
     and binds whatever it matches as `var`.
     The type of `var` will be the same as `(?<var>...)`.
 
-  - `(N?<var as name>)` gets substituted by the value of the globally defined string variable named `var`,
-    and binds whatever it matches as `name`.
+  - `(?&name:var>)` same as above but binds whatever it matches as `name`. (shortcut for `(?<v>(?&qname))`)
     The type of `name` will be the same as `(?<var>...)`.
 
-  - `(U?<var>)` gets substituted by the value of the globally defined string variable named `var`,
-    and does not bind its match to any name.
-
   - `?<var>` at the start of a pattern binds group 0 as `var : string`.
     This may not be the full string if the pattern is unanchored.
 

ppx_regexp_extended.opam

@@ -40,9 +40,8 @@ below an optionally matched group.
 
 Additional extensions:
 
-- `(?N<var>)` and `(?N<var as name>)` provide named substitution, and make the
+- `(?&var)` and `(?&name:var)` provide named substitution, and make the
 matched substring available in the right-hand side of match cases
-- `(?U<var>)` marks groups whose substrings are not needed in the right-hand side
 - `let%pcre name = {|re|}` defines reusable patterns for use within `(?U/N<name>)` patterns
 - `match%mikmatch` supports mikmatch-style syntax with typed captures and pattern
 composition, along with `let%mikmatch` for defining reusable patterns