User Guide

Testing and Maintaining Web Pages 117
Expression examples
The following examples show some regular expressions and describe what they match
Resources
An excellent reference on regular expressions is Mastering Regular Expressions by
Jeffrey E.F. Friedl, published by O'Reilly & Associates, Inc.
Expression Description
[\?&]value=
A URL parameter value in a URL
[A-Z]:(\\[A-Z0-9_]+)+
An uppercase DOS/Windows full path that (a) is not the
root of a drive, and (b) has only letters, numbers, and
underscores in its text
[A-Za-z][A-Za-z0-9_]*
A ColdFusion variable with no qualifier
([A-Za-z][A-Za-z0-9_]*)(\.[A
-Za-z][A-Za-z0-9_]*)?
A ColdFusion variable with no more than one qualifier,
for example, Form.VarName, but not
Form.Image.VarName
(\+|-)?[1-9][0-9]*
An integer that does not begin with a zero and has an
optional sign
(\+|-)?[1-9][0-9]*(\.[0-9]*)
?
A real number
(\+|-)?[1-9]\.[0-9]*E(\+|-)?
[0-9]+
A real number in engineering notation
a{2,4}
Two to four occurrences of "a": aa, aaa, aaaa
(ba){3,}
At least three "ba" pairs: bababa, babababa, ...