Thanks for clarifying.

Here are some more examples for those reading later and who haven't previously had to work with non-printing characters in this way (e.g. me a few hours ago):

#  default $; does not print
perl -e 'print join $;, 1..5'
12345

#  but $; is still in the string
perl -e '@x = split ($;, join ($;, 1..5)); print join ":", @x'
1:2:3:4:5
[download]

That still does leave the issue of debugging using print statements, as [5,55] and [55,5] will both print as 555 on a terminal. The point is effectively moot, though, as the other posts have shown multidimensional indexing is slower and should probably not be used in this case.