From: Brian Candler <B.Candler@...>
Date: 2003-04-27T19:10:53+09:00
Subject: Re: File reading and line continuation with '\'

On Sun, Apr 27, 2003 at 09:39:00AM +0900, Jim Freeze wrote:
> > cat a
> one\
> two
> irb(main):001:0> a=File.read("a")
> => "one\\\ntwo\n"
> irb(main):002:0> b=File.readlines("a")
> => ["one\\\n", "two\n"]
> 
> I would like instead:
>  
>  f=File.readlines("a")
>  ["onetwo\n"]

I guess the simplest is to read the whole file in and process it by removing
backslash-newline sequences:

a=File.read("a").gsub!(/\\\n/,'')
a=a.split(/\n/)

The split also removes the \n from each result line. Use

a=a.scan(/.*?\n/)

if you want to keep them (although that will miss the last line if the last
character of the file is not a newline)

You could perhaps also split the string on a regexp which is \n with a
look-behind assertion saying that it's not preceeded by a backslash.
Personally I consider such things to be an abuse of regexps :-) In any case,
that will leave the backslash-newline sequence within the result string,
which you didn't want.

Also, the Pickaxe book doesn't indicate that Ruby has look-behind assertions
(but it does have look-ahead assertions)

Regards,

Brian.