5.  ()==/./g;: The RHS of a list assignment operator is evaluated in list context.

Visually tricky, this is actually a pointless comparison evaluating in void/scalar context:

c:\@Work\Perl>perl -wMstrict -le
"$_ = 'abc';
 ()== /./g;
 /(.)/g;
 print qq{'$1'};
"
Useless use of numeric eq (==) in void context at -e line 1.
Use of uninitialized value in numeric eq (==) at -e line 1.
'b'
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