From: Calamitas <calamitates@...>
Date: 2008-07-09T18:25:33+09:00
Subject: Re: 'ab\c' and 'ab\\c'

On Wed, Jul 9, 2008 at 11:00 AM, Max Williams
<toastkid.williams@gmail.com> wrote:
> I think you stumbled on another special character, \c, which seems to
> have some weird properties:
>
> -in single quotes, must be followed by another character, but when it
> is, just swaps the \ for a \\
>
> -in double quotes, again must be followed by another character, which it
> translates into a number, though by what scheme i have no idea:

In a double-quoted string, \c followed by another character forms a
control character. Control characters are character codes 0 to 31 in
the ASCII character set. When you call inspect on a string (as irb
does for you), Ruby escapes these control characters and those are the
number you are seeing.

In a single-quoted string, \c doesn't do anything, just like "The Ruby
programming language" says. Irb gets confused here and does interpret
the \c, thinks the string goes on while it doesn't, asks more input
until a quote is given, which really starts a new string which is then
unterminated and that's the error you get.

It's a bug in irb.

Peter