$n=4; 
print $n." -- ".(--$n||'no more'),".\n" while $n;

# output on perl 5.26 5.24 and before
4 -- 3.
3 -- 2.
2 -- 1.
1 -- no more.

# output on perl 5.28
3 -- 3.
2 -- 2.
1 -- 1.
0 -- no more.