All avaliable regexp packages treat matching as single matching function, for example the javascript built-in regexp, you either matche the entire regexp or you fail. This package provides a more flexible approach will return one of 4 states
| Status | Description |
|---|---|
| DONE | String matches completely |
| OK | The regexp matches, but will accept more characters, for example a zip code may be 5 digits or 9 digits |
| PARTIAL | The regexp matches the string so far but is incomplete, i.e. needs more characters |
| FAIL | The string does not match the regexp |
using the zipcode exmple
Reg Expression : [0-9]{5}-[0-9]{4} :
| String | Status |
|---|---|
| "90" | PARTIAL |
| "90210" | OK |
| "90210-5" | PARTIAL |
| "90210-5003" | DONE |
| "90210-500A" | FAIL |
This is a brief explanation of the algorithm. Suppose we have the following regexp [a-z][0-9]-[0-9]|cat|dog
we parse the regexp to create the following tree:
We process the the tree to get the following graph:
