Character |
Usage |
* |
Matches the previous character
zero or more times |
+ |
Matches the previous character
one or more times |
? |
Matches the previous character
zero or one times |
. |
Matches any single character
except the newline |
^ |
Matches the start of the
input |
$ |
Matches the end of the input
|
x|y |
Matches either first or
second character listed |
(pattern) |
Matches pattern |
{number} |
Matches exactly number
times |
{number,} |
Matches number, or
more, times (note comma) |
{num1, num2} |
Matches at least num1
and at most num2 times |
[abc] |
Matches any character listed
between the [ ] |
[^abc] |
Matches all characters except
those listed between the [ ] |
[a-e] |
Matches any characters in
the specified range (a,b,c,d,e) |
[^K-Q] |
Matches all characters except
in the specified range |
\ |
Signifies that the next
character is special or a literal. |
\b |
Matches only on a word boundary
|
\B |
Matches only inside a word
|
\d |
Matches only on a digit
|
\D |
Matches only on a non-digit
|
\f |
Matches only on a form feed
character |
\n |
Matches only on a new line
|
\r |
Matches only on a carriage
return |
\s |
Matches only on a blank
space |
\S |
Matches only on nonblank
spaces |
\t |
Matches only on a tab |
\v |
Matches only on a vertical
tab |
\w |
Matches only
on A to Z, a to z, 0 to 9, and _ |
\W |
Matches characters
other than A to Z, a to z, 0 to 9, and _ |
\number |
Matches any positive number
|
\octal |
Matches any octal number
|
\xhex |
Matches any hexadecimal
number (x is required) |