From: Gavin Sinclair <gsinclair@...>
Date: 2003-11-27T15:23:50+09:00
Subject: Re: Backtrace without skips needed

On Wednesday, November 26, 2003, 7:47:10 PM, Tobias wrote:

> Is there a way to tell ruby that it must never skip levels in the 
> backtrace like this:

> /lib/ruby/1.8/net/ftp.rb:192:in `readline': End of file reached (EOFError)
>          from /lib/ruby/1.8/net/ftp.rb:192:in `getline'
>          from /lib/ruby/1.8/net/ftp.rb:202:in `getmultiline'
>          from /lib/ruby/1.8/net/ftp.rb:216:in `getresp'
>          from /lib/ruby/1.8/net/ftp.rb:232:in `voidresp'
>          from /lib/ruby/1.8/net/ftp.rb:157:in `connect'
>          from /lib/ruby/1.8/net/ftp.rb:155:in `synchronize'
>          from /lib/ruby/1.8/net/ftp.rb:158:in `connect'
>          from /lib/ruby/1.8/net/ftp.rb:119:in `initialize'
>           ... 7 levels...
>          from getp.rb:85:in `get_from'
>          from getp.rb:85:in `open'
>          from getp.rb:85:in `get_from'
>          from getp.rb:120


If you catch the exception ('err') and 'puts err.backtrace', you'll
get the full story in the following form:

  ...
  e.rb:7:in `b'
  e.rb:3:in `a'
  e.rb:7:in `b'
  e.rb:3:in `a'
  e.rb:7:in `b'
  ...
  
If you do a more complicated printing routine as Matz suggested, you
get this:

        ...
        from e.rb:7:in `b'
        from e.rb:3:in `a'
        from e.rb:7:in `b'
        from e.rb:3:in `a'
        from e.rb:7:in `b'
        from e.rb:3:in `a'
        ...

For information purposes, I'd just 'puts err.backtrace' and be done
with it.  Note in both cases, the full trace is printed, not "..."!

Gavin