When composing your regular expression search pattern, you created a pattern element with an illegal repetition factor. For example, the pattern
/^+/
is illegal because the element ^ (beginning of input) cannot have a repetition factor. The following table lists the elements that cannot have repetition factors.
| Element | Description |
|---|---|
| ^ | Beginning of input |
| $ | End of input |
| \b | Word boundary |
| \B | Non-word boundary |
| * | Zero or more repetitions |
| + | One or more repetitions |
| ? | Zero or one repetitions |
| {n} | n repetitions |
| {n,} | n or more repetitions |
| {n,m} | From n to m repetitions, inclusive |
To correct this error
Ensure your search pattern element contains legal repetition factors only.