Your solution is still wrong as proposed: 

/^[:alpha:][[:alpha:]\d-]*\z/

[download]

The first mistake is that [:alpha:], by itself isn't a character class. It won't compile as you've written it. It needs to be presented like this: 

[[:alpha:]]
^_________^______Note the outer set of brackets.

[download]

The next problem is that the OP stated that the first character cannot be a hyphen character, but he didn't exclude numeric digits. Your solution will fail if the first character is a numeric digit.

Also, '^' matches at the beginning of a "line". That probably isn't an issue for this particular regexp, but it is worth noting that '^' is different from '\A', which matches at the beginning of a string.

If you really despise the /x modifier, and prefer to avoid [:digit:] for whatever reason (maybe less typing?), you could rewrite my original solution like this: 

m/\A[[:alpha:]\d][[:alpha:]\d-]*\z/

[download]

But I think the version with the /x modifier is easier to read since it keeps individual anchors together, and everything else separate.


Dave

In reply to Re^4: Regular Expression - Need HElp..pls by davido
in thread Regular Expression - Need HElp..pls by dani_cv_perl

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