Here's another example:

# foo.pl
use strict;
use warnings;

require 'bar.pl';

frobozz( 2 );

__END__


# bar.pl
use strict;
use warnings;

{
  my $x;    # same thing with "my $x = 'whatever';"

  frobozz( 1 ) unless caller;

  sub frobozz {
    ( $x ) = @_;
    print 'NOT ' unless defined eval( '$x' );
    print "OK\n";
    quux();
  }

  sub quux {
#    $x = $x;
    print 'NOT ' unless defined eval( '$x' );
    print "OK\n";
  }
}

1;

__END__

[download]
If one runs foo.pl, the output is 
OK
NOT OK
...meaning that frobozz sees $x but quux doesn't. If one uncomments the commented line in quux or runs bar.pl directly, the output is 
OK
OK

(This is true for both 5.8.6 and 5.8.8 on Linux.)

After re-reading the docs on eval, I can't see how a programmer can be expected to predict this behavior. Therefore, it is, at the very least, a design bug, IMO.

the lowliest monk

In reply to Re: "eval" and "my" variable weirdness by tlm
in thread "eval" and "my" variable weirdness by splinky

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