User Guide

Using regular expressions 109
• Any regular expression can be followed by one of the following suffixes:
− {m,n} forces a match of m through n (inclusive) occurrences of the preceding
regular expression
− {m,} forces a match of at least m occurrences of the preceding regular
expression
The syntax {,n} is not allowed.
• A range of characters can be indicated with a dash. For example,
[a-z] matches
any lowercase letter. However, if the first character of the set is the caret (^), the
RegExp matches any character except those in the set. It does not match the
empty string. For example,
[^akm] matches any character except a, k, or m. The
caret loses its special meaning if it is not the first character of the set.
• All regular expressions can be made case-insensitive by substituting individual
characters with character sets, for example,
[Nn][Ii][Cc][Kk].
Using a character class
You can specify a character by using a POSIX character class. You enclose the
character class name inside two square brackets, as in this example:
"Macromedia’s Website","[[:space:]]","*","ALL")
This code replaces all the spaces with *, producing this string:
Macromedia’s*Website
The following table shows the supported POSIX character classes:
Character
class Matches
alpha Any letter, [A-Za-z]
upper Any uppercase letter, [A-Z]
lower Any lowercase letter, [a-z]
digit Any digit, [0-9]
alnum Any alphanumeric character, [A-Za-z0-9]
xdigit Any hexadecimal digit, [0-9A-Fa-f]
space A tab, new line, vertical tab, form feed, carriage return, or space
print Any printable character
punct Any punctuation character:
! ‘ # S % & ‘ ( ) * + , - . / : ; < = > ? @ [ / ] ^ _ { | } ~
graph Any character defined as a printable character except those defined as
part of the space character class
cntrl Any character not part of the character classes:
[:upper:], [:lower:], [:alpha:], [:digit:], [:punct:], [:graph:], [:print:], [:xdigit:]