Perl optimisation help

[G. Matthew Rice]

david thornton <david-FkEgs2FKm2NvBvnq28/GKQ at public.gmane.org> writes:
> >Faster would be
> >
> >    { local $/; $var = <INPUT>; }
> 
> I realize there's not much to it, but can you walk us through "local $/" ? I
> love brief code, just it's sometimes hard to understand.

Well, let's break it up:

{                 # Start a new block (and new scope)
  local $/;       # Define a locally scoped variable called $/ initialized to
                  # undef.  This is the 'input record separator' which is
                  # a '\n' by default.
  $var = <INPUT>; # Since 'nothing' separates records, the first read will
                  # read in everything.
}                 # end of scope; $/ goes back to whatever it was before. 

You should do a little reading up on what 'local' means, too.  There are a
number of scopes for variables in perl; global, local, my, our. (did I miss
any?).

HTH,
-- 
g. matthew rice <matt-s/rLXaiAEBtBDgjK7y7TUQ at public.gmane.org>           starnix, toronto, ontario, ca
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