@a = 1 .. 1e6;;
print total_size \@a;;
32000176

"$_" for @a;;
Useless use of string in void context at (eval 11)
print total_size \@a;;
72000176

@a = 1 .. 1e6;;
print total_size \@a;;
32000176
''.$_ for @a;;
Useless use of concatenation (.) or string in void context at (eval 15)

print total_size \@a;;
72000176