Better table

Author: cmccomb

README.md

@@ -37,4 +37,59 @@ The eventual goal of this crate is to support all of the syntax in the [core Rus
 |               |`\pN`       | One-letter name Unicode character class |
 |               |`\p{Greek}` | Unicode character class (general category or script) |
 |               |`\PN`       | Negated one-letter name Unicode character class |
-|               |`\P{Greek}` | negated Unicode character class (general category or script) |
+|               |`\P{Greek}` | negated Unicode character class (general category or script) |
+
+### Perl Character Classes
+
+| Implemented?       | Expression | Description |
+| :---------------:  | :--------: | :---------- | 
+| `digit()`          |   `\d`     | digit (\p{Nd}) |
+| `non_digit()`      |   `\D`     | not digit |
+| `whitespace()`     |   `\s`     | whitespace (\p{White_Space}) |
+| `non_whitespace()` |   `\S`     | not whitespace |
+| `word()`           |   `\w`     | word character (\p{Alphabetic} + \p{M} + \d + \p{Pc} + \p{Join_Control}) |
+| `non_word()`       |   `\W`     | not word character |
+
+### ASCII Character Classes
+
+| Implemented?       | Expression | Description |
+| :---------------:  | :------------: | :---------- |
+|                    | `[[:alnum:]]`  | alphanumeric ([0-9A-Za-z]) |
+|                    | `[[:alpha:]]`  | alphabetic ([A-Za-z]) |
+|                    | `[[:ascii:]]`  | ASCII ([\x00-\x7F]) |
+|                    | `[[:blank:]]`  | blank ([\t ]) |
+|                    | `[[:cntrl:]]`  | control ([\x00-\x1F\x7F]) |
+| `digit()`          | `[[:digit:]]`  | digits ([0-9]) |
+|                    | `[[:graph:]]`  | graphical ([!-~]) |
+|                    | `[[:lower:]]`  | lower case ([a-z]) |
+|                    | `[[:print:]]`  | printable ([ -~]) |
+|                    | `[[:punct:]]`  | punctuation ([!-/:-@\[-`{-~]) |
+|                    | `[[:space:]]`  | whitespace ([\t\n\v\f\r ]) |
+|                    | `[[:upper:]]`  | upper case ([A-Z]) |
+|  `word()`          | `[[:word:]]`   | word characters ([0-9A-Za-z_]) |
+|                    | `[[:xdigit:]]` | hex digit ([0-9A-Fa-f]) |
+
+## Repetitions
+
+| Implemented?       | Expression | Description |
+| :---------------:  | :------------: | :---------- |
+x*        zero or more of x (greedy)
+x+        one or more of x (greedy)
+x?        zero or one of x (greedy)
+x*?       zero or more of x (ungreedy/lazy)
+x+?       one or more of x (ungreedy/lazy)
+x??       zero or one of x (ungreedy/lazy)
+x{n,m}    at least n x and at most m x (greedy)
+x{n,}     at least n x (greedy)
+x{n}      exactly n x
+x{n,m}?   at least n x and at most m x (ungreedy/lazy)
+x{n,}?    at least n x (ungreedy/lazy)
+x{n}?     exactly n x
+
+## Composites
+
+| Implemented?       |   Expression   |      Description                |
+| :---------------:  | :------------: | :------------------------------ |
+|    `+`             |   `xy`         | concatenation (x followed by y) |
+| `or()`             |   `x\|y`        | alternation (x or y, prefer x)  |
+