I was wondering if someone would be kind enough to explain the following to me: 
sub x
{
   ('a', 'b', 'c', 'd');
}

sub a
{
   { x };
}

sub b
{
   $x = { c };
}

sub c
{
   { 'a', 'b', 'c', 'd' };
}

sub d
{
   { ('a', 'b', 'c', 'd') };
}

print a, "\n";
print b, "\n";
print c, "\n";
print d, "\n";

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subroutine 'a' returns a list, where subroutine 'b' returns a hash reference. It seems to me that they should both return a hash reference. I noticed this behavior when I had code that stated out as 

{
    a => 'b',
    c(),
}

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and then removed the a => 'b'. This caused code to break as the sub routine started returning a list instead of a hash reference.
-- gam3
A picture is worth a thousand words, but takes 200K.

In reply to When is a hashreference a subexpresion? by gam3

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