^ | Matches the beginning of line |
$ | Matches the end of line |
. | Mathes any character |
\s | Matches whitespace; equivalent to [\t\n\r\f\v] |
\S | Matches any NON-Whitespace; equivalent to [^\t\n\r\f\v] |
* | Zero or more time; Repeats a character |
*? | Zero or more times; NON-GREEDY; Repeats a character |
+ | One or More times; Repeats a character |
+? | One or More times; NON-GREEDY; Repeats a character |
[aeiou] | Matches a single character in the listed set |
[^XYZ] | Matches a single character NOT in the listed set |
[a-z0-9] | A set of character or an include range |
( | Indicates where the string extraction starts |
) | Indicates where the string extraction ends |
a|b | matches either a or b, a and b are string matching pattern |
\ | Escape character for special characters (\t, \n, \b) |
\b | Matches word boundary |
\d | Matches single digit; equivalent to [0-9] |
\w | Alphanumeric character; [a-zA-Z0-9_] |
\W | NON-Alphanumeric character; [^a-zA-Z0-9_] |
? | Matches zero or One occurances |
{n} | Exactly n repetitions, n>=0 |
{n,} | Atleast n repeatitions |
{,n} | Atmost n repeatitions |
{m,n} | Atleast m times and atmost n repeatitions |