Regular Expression Summary

The following special characters are interpreted in regular expressions

Table 3.7: Regular Expression Characters

Character

Matches

^ (at the beginning only)

beginning of line

.

any single character. In multi-line mode, this also matches the end-of-line character.

[abc]

any single character that belongs to the set abc

[^abc]

any single character that does not belong to the set abc

*

zero or more occurrences of the preceding character

+

one or more occurrences of the preceding character

\t

a tab character

\s

a space character

\w

white space (a tab or a space char­acter)

\n

new-line, or the end-of-line charac­ter. Use this if you want to match a line break in the middle of a pat­tern.

$

the end of the line

Sets, such as [abc] may be in the following formats.

Table 3.8: Regular Expression Sets

Set type

Meaning

[<character list>]
eg.  [abcde]

Matches any character within the set. The set can be any number of characters long.

[x-y]
eg. [a-z]

Matches on any character within the range of x through y, inclu­sively. The ASCII value of x must be less than that of y.

combination;
eg. [WXYa-z0-9]

Character lists and ranges may be combined.