I started to wondering about this a while ago. There was once a post, which reported his/her discovery that Perl 5.8 has a bug on supporting subs running on its own thread, and returning array or hash. The problem is that the hash or array would be evaluated as if in a scalar context. (Well, there is a workaround, just to return ref to hash or array. In your mind, this workaround is actually even better, as by returning ref, you gain performance quite significantly.)

Now back to my question. When you evaluate array in a scalar context, for example: 
@a = (1,2,4,6,8);
$a = @a;
print $a;

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It gives you a FIVE, which is quite easy to understand, as it matches $#a.

However, if you do, 
%a = (a=>1,b=>2,c=>4,d=>6,e=>8);
$a = %a;
print $a;

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It gives you 5/8. Now I don't understand, what does this number or fraction or whatever mean?

In reply to what does that value mean, when you evaluate hash in a scalar context? by pg

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