| 8. 1. 6. Match a particular character a specified number of times. |
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There are two general ways the repetition operators work. |
One class of operators is greedy, that is, they match as much as they can, until the end. |
The other class is reluctant (or lazy), and matches only to the first chance they can terminate. |
For example, the regular expression .*; matches any number of characters up to the last semicolon it finds. |
To only match up to the first semicolon, the reluctant version .*?; must be used. |
| Greedy Operator | Description | | X? | Matches X zero or one time | | X* | Matches X zero or more times | | X+ | Matches X one or more times | | X{n} | Matches X exactly n times, where n is any number | | X{n,} | Matches X at least n times | | X{n,m} | Matches X at least n, but no more than m times |
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| Reluctant (Lazy) Operator | Description | | X?? | Matches X zero or one time | | X*? | Matches X zero or more times | | X+? | Matches X one or more times | | X{n}? | Matches X exactly n times, where n is any number | | X{n,}? | Matches X at least n times | | X{n,m}? | Matches X at least n, but no more than m times |
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