in reply to Conditional use of 'use'

Since use module is the same as 
BEGIN { require module }

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, you could do something like:
BEGIN {
  my $version = (($0 =~ /2(?:\.pl)?$/) ? '2' : '');
  require "LayerB${version}.pm";
}

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If you are using the form use module LIST you'll need to call import:
BEGIN {
   # set $version based on $0
  require "LayerB${version}.pm";
  "LayerB${version}"->import(qw(A B C));
}

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update: added import part, cleaned up $version setting

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Re: Re: Conditional use of 'use'
by dvergin (Monsignor) on Jun 12, 2001 at 09:08 UTC
    Camel 3, p. 822 (which I had already consulted), says: BEGIN { require MODULE; import MODULE LIST; } What about the import? Needed? Not? The modules are pure OO. And no @EXPORT (if that is relevant).
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[d/l]
      You've asked the right question. If you only ever use the OO interface and if you don't export anything from the modules, you don't need to import anything explicitly.
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      Then you can just do: 

      if ($version == 2) {
     require LayerB2;
}
else {
     require LayerB;
}

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              - tye (but my friends call me "Tye")
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[d/l]

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