Apparently (undef)[0] is being interpreted as a null list. In the context of the other statements, why is that? Thanks...

%tmp= (nothing => undef, one => 1);
# $tmp{nothing} is undef

%tmp= (nothing => (0, undef)[0], one => 1);
# $tmp{nothing} == 0 

%tmp= (nothing => [undef, 0]->[0], one => 1);
# $tmp{nothing} is undef 

%tmp= (nothing => scalar ((0, undef)[1]), one => 1);
# $tmp{nothing} is undef 

%tmp= (nothing => (undef), one => 1);
# $tmp{nothing} is undef 

%tmp= (nothing => (undef)[0], one => 1);
# $tmp{nothing} eq 'one'*** Why not undef?

%tmp= (nothing => (undef, 0)[0], one => 1);
# $tmp{nothing} eq 'one'*** Why not undef?

1;
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