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A comment on Show HN: Regex Cheatsheet.

Re:Show HN: Regex Cheatsheet by Amarok on Friday January 31, 2020 @09:24AM (#22201857)
^[a-z0-9_-]{3,15}$

The username reference doesn't match 16 characters as claimed

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Re:Show HN: Regex Cheatsheet by geongeorgek on Friday January 31, 2020 @09:48AM (#22202048)
I should match. the number 15 there means that repeat x up to 15 times. so 1+15=16.

looks good to me

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Re:Show HN: Regex Cheatsheet by aratauto on Friday January 31, 2020 @10:09AM (#22202233)
That is not correct. 15 is total maximum number of repeats including the first one. Even the diagram on https://ihateregex.io/expr/username correctly says that loop can be taken between 2 and 14 times.
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Re:Show HN: Regex Cheatsheet by asicsp on Friday January 31, 2020 @09:54AM (#22202098)
where does the extra 1 come from? a{2,5} means match 'a' two to five times
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