learn PPI 1: double to single

well, I'm very strict on Perl code (more than use strict;).
I want code like my $a = "a"; becomes my $a = 'a'; since it's better.
I'm not considering the speed since it's trivial for " to '. but u'd admit, 'a' is faster than "a".

PPI is really amazing.
it breaks Perl code down into the Perl document/structure we can read and analyze.

To do the task above. I just wrote a script based on PPI.
http://fayland.googlecode.com/svn/trunk/script/learn_ppi/01DoubleToSingle.pl
OK, it's my first time try with PPI, and it's really easy to understand and coding.

Many thanks to Adam Kennedy.

next time, I think I'll deal with
if ( $a eq 'a' ) {
to
if ( 'a' eq $a ) {

I think it's fun. and good to learn a new good thing.

Enjoy and have fun.