Moved the last "}" at 176; placed it below the "return 1;"
because, oddly,

F:\_wo\pl_test>perl -c prettyprinter.pl
prettyprinter.pl syntax OK

but

F:\_wo\pl_test>perl prettyprinter.pl
Can't return outside a subroutine at prettyprinter.pl line 180.

WTF?

Also, think you need to UNcomment the "use" statements at the top... and maybe use warnings and strict?

...and having done all those, I've run out of time to psych out this:

Useless use of a constant in void context at prettyprinter.pl line 6, <DATA> line 164.

Still, I'm impressed. ++