[:digit:]

[Stephen J. Turnbull]

Jerry James writes:

 > Do we not support the use of [:digit:]?

No, we don't.  Supporting the POSIX character classes properly in Mule
is nontrivial, and nobody has ever been willing to work on it.

You can get broken (ASCII-only) support based on a patch that was
submitted a couple of months ago, but if you want it in the mainline
it needs to support the whole Mule repertoire more or less sanely.