Uh... well, yeah, it is a new example of something.

Please share the 'of what' as I can't see the relevance in a thread devoted to encoding/decoding utf8.

Oh, yes. When I print the part you've labeled as non-printing, I see this:

#!/usr/bin/perl
use strict;
use warnings;
# 1046930

my $string = "This is what you have" . "\n";;
print $string;

#this part does not print:

substr($string, 5, 2) = "wasn't";         #change "is" to "wasn't"
print $string . "\n";

substr($string, -12) = "ondrous";        #"this wasn't wondrous"
print $string . "\n";


substr($string, 0, 1) = "";            #delete first character
print $string . "\n";


substr($string, -10) = "";            #delete last 10 characters
print $string . "\n";


#printing problem end here


=head out:

This is what you have
This wasn't what you have

This wasn't whondrous
his wasn't whondrous
his wasn't

=cut
[download]

...which is at some variance with what your comments suggest you expected.