:)

In scalar context the null list as lvalue counts (accumulates and returns number of elements )

$ perl -e " @g=( 1 .. 4 ); $f[0]=()=@g; dd\@f; dd\@g "
[4]
[1 .. 4]
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In list context the null list as lvalue is null (accumulates and discards )

$ perl -e " @g=( 1 .. 4 ); @f=()=@g; dd\@f; dd\@g "
[]
[1 .. 4]
[download]