Is there a dedicated quantifier for exact occurrences in regular expressions?

Quantifiers for Exact Occurrences of X

In regular expressions, quantifiers are used to specify the occurrence of a pattern. The provided regular expression:

X{n}|X{m}

aims to test whether the pattern X occurs exactly n or m times. While this approach can work, it raises the question of whether there's a dedicated quantifier for this purpose.

Custom Quantifiers

In general, there's no single quantifier that fulfills this specific requirement. However, the method you've proposed is an effective solution.

An Alternate Approach

An alternative approach to testing for exact n or m occurrences involves using the following pattern:

X{m}(X{k})?

where m is less than n and k is the difference between n-m. This pattern matches X exactly m times, followed by an optional match of X k times.

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