Regular expression in Mapfile

[Christopher R. Thorne]

Hello,
I am working on classifying land us polygon layers and I wish to us 
regular expressions. I have searched the archive and it came up short 
for what I am looking for. The mapfile reference also was a little 
skimpy. ;)

I would like to define an expression the finds values (4100, 4200, 4300 
4400 4500) and place these features in a single class. What would be the 
best (least expensive) expression?

For example,

CLASS
   EXPRESSION /[4000-4501]/
END

(I am not even sure if I have defined this correctly.)

Also, does anyone have a good reference to regex?

Chris


-- 
Christopher R. Thorne, GIS Specialist
--
christhorne at sympatico.ca
Tel:(613)523-6593