From: Ammar Ali <ammarabuali@...>
Date: 2010-10-28T16:50:37+09:00
Subject: ctype functionality without a gem?

Hello,

Is there a built-in method for identifying character types a la
ctype() in C? I would like to avoid requiring a gem dependency.

I'm considering the following approach, if nothing exists, but it
seems like overkill to me.

def ctype(c)
  case c
  when /[[:alnum:]]/; :alnum
  when /[[:alpha:]]/; :alpha
  # etc...
  end
end

def alnum?(c); ctype(c) == :alnum end
def alpha?(c); ctype(c) == :alpha end
# etc...

Also, it requires some 1.8 vs 1.9 special cases for 'ascii' and
'word', if not more.

Regards,
Ammar