README.md in regexp-examples-0.2.2 vs README.md in regexp-examples-0.2.3
- old
+ new
@@ -34,10 +34,11 @@
* Non-capture groups, e.g. `/(?:foo)/`
* Capture groups, e.g. `/(group)/`
* Including named groups, e.g. `/(?<name>group)/`
* ...And backreferences(!!!), e.g. `/(this|that) \1/` `/(?<name>foo) \k<name>/`
* Groups work fine, even if nested! e.g. `/(even(this(works?))) \1 \2 \3/`
+* Control characters, e.g. `/\ca/`, `/\cZ/`, `/\c9/`
* **Arbitrarily complex combinations of all the above!**
## Not-Yet-Supported syntax
I plan to add the following features to the gem, but have not yet got round to it:
@@ -46,10 +47,9 @@
* POSIX bracket expressions, e.g. `/[[:alnum:]]/`, `/[[:space:]]/`
* Options, e.g. `/pattern/i`, `/foo.*bar/m`
* Escape sequences, e.g. `/\xa1/`
* Unicode characters, e.g. `/\u06E9/`
* Named properties, e.g. `/\p{L}/` ("Letter"), `/\p{Arabic}/` ("Arabic character"), `/\p{^Ll}/` ("Not a lowercase letter")
-* Control characters, e.g. `/\cA/` ... `/\cZ/`
* Subexpression calls, e.g. `/(?<name> ... \g<name>* )/` (Note: These could get _really_ ugly to implement, and may even be impossible, so I highly doubt it's worth the effort!)
## Impossible features ("illegal syntax")
The following features in the regex language can never be properly implemented into this gem because, put simply, they are not technically "regular"!