From: Robert Klemme <shortcutter@...>
Date: 2011-09-22T22:56:06+09:00
Subject: Re: RegEx Help For checking alphnumeric

On Thu, Sep 22, 2011 at 3:43 PM, Adam Prescott <adam@aprescott.com> wrote:
> On Thu, Sep 22, 2011 at 2:35 PM, Saurabh A. <getsauin@gmail.com> wrote:
>
>> Is this right.
>>
>> str.match(/(\w)(\d+)(\d+)/)
>
>
> Using Rubular is a good way of quickly checking regular expressions:
> http://rubular.com/r/0VTmjIcQ7j
>
> Note that \d+\d+ is almost redundant, but you'll actually not match "v3".

Folks, you forgot anchoring and also that \w matches more than just characters:

irb(main):006:0> /\w+\d+/ =~ '++++_0344'
=> 4
irb(main):007:0> /\w+\d+/ =~ '_1'
=> 0

So better match (!) for the criterion given is

/\A[a-z]\d+\z/i =~ s
/\A\p{Alpha}\d+\z/ =~ s # on 1.9 and on

Saurabh, I recommend the book "Mastering Regular Expressions".  There
are also quite a few tutorials on the web.

Kind regards

robert


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