Thanks to your explanation, I understand "strict refs" allows the following: 
my $runable = \&{ 'run' };
&$runable;

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Your code shows how we avoid throwing exceptions. I think, however, it's still unclear why defined/undef &{ 'run' } doesn't throw exceptions while "strict refs".

In reply to Re^2: undef/defined &{$name} while "strict refs" by anazawa
in thread undef/defined &{$name} while "strict refs" by anazawa

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