^ | Beginning of a line |
$ | End of a line |
. | Any character |
Expression? | The expression zero or one times |
Expression* | The expression zero or more times |
Expression+ | The expression one or more times |
Expression{n} | The expression n times |
Expression{n,} | The expression at least n times |
Expression{n,m} | The expression at least n but no more than m times |
Expression1|Expression2 | The expression1 or the expression2 |
(Expression) | The expression within the brackets |
\1 \2 ... \n | The content of the nth bracket |