-r--r--r--   1 yourname       8318 Jan 30  1996 file1.txt
-r--r--r--   1 yourname      11986 Jan 30  1996 file2.txt
-r--r--r--   1 yourname      46852 Feb 27  1996 file3.txt
-r--r--r--   1 yourname      72698 Feb 27  1996 file4.txt

##</code><code>##

@sorted_by_size = 
  map { $_->[0] } 
  sort { $a->[1] <=> $b->[1] } 
  map { [$_, -s] } 
  @files;

##</code><code>##

1. Map the initial list into a list of ref to lists with the original and modified values 
2. Sort the list of references 
3. Map the list of ref back into a plain list with the initial values