I don't get it. Instead of
    say for do { my @arr = @arr[ 0 .. $#arr - 1 ]; @arr};
et al, why not just
    say for do { @arr[ 0 .. $#arr-1 ] };
or (much) better yet...

>perl -wMstrict -lE
"my @arr = qw{ one two three four };
 say for @arr[ 0 .. $#arr-1 ];
 say qq{@arr};
"
one
two
three
one two three four
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