Using explicitly numbered repetition instead of question mark, star and plus

Posted by polygenelubricants on Stack Overflow See other posts from Stack Overflow or by polygenelubricants
Published on 2010-06-13T14:39:02Z Indexed on 2010/06/13 14:42 UTC
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best-practices

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regex

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pattern-matching

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readability

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repetition

I've seen regex patterns that use explicitly numbered repetition instead of ?, * and +, i.e.:

Explicit            Shorthand
(something){0,1}    (something)?
(something){1}      (something)
(something){0,}     (something)*
(something){1,}     (something)+

The questions are:

Are these two forms identical? What if you add possessive/reluctant modifiers?
If they are identical, which one is more idiomatic? More readable? Simply "better"?

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