Michael W. Ryder wrote:
> As part of a method I am playing with while learning Ruby I need to be 
> able to determine which characters in a string are non-printable.  What 
> is the "best" method for determining if a character is printable, such 
> as an "A", or unprintable, such as a tab?
> While I could create a list of printable characters using ranges is this 
> the best way to do this?
> 
The POSIX character classes are for exactly this:

irb(main):001:0> "A \n B \t C".gsub(/[[:graph:]]/, '')
=> " \n  \t "
irb(main):002:0> "A \n B \t C".gsub(/[[:print:]]/, '')
=> "\n\t"

-- 
Alex