Athanasius clarified what I wanted to say. Thanks a lot :) By the way, the following is equivalent to the code in question: 
no strict 'refs';
my $walkable = defined *{ 'walk' }{CODE};

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In this case, "no strict refs" is required and it seems reasonable. Should we cosider defined &{ 'walk' } not to be a recommended expression?

In reply to Re^9: undef/defined &{$name} while "strict refs" by anazawa
in thread undef/defined &{$name} while "strict refs" by anazawa

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