Without the use statement I get: 
No such class wolf at demo.pl line 22, near "my wolf"
syntax error at demo.pl line 22, near "my wolf="

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The reason for this error message is a bit more obscure. (It has to do with something called "indirect object syntax".) However, the error goes away if turn the bareword wolf into the scalar $wolf. 
  my $wolf=new sheep;
     ^

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I suspect this is what you had in mind.

In reply to Re: Re: Re: Simple OO by dws
in thread Simple OO by lzcd

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