With that regexp you'll get an extra space at the end if the line is an even multiple of your breaking width. This handles that case: 

my $width = 8;
my $break_at = 4;

my $orig = "#" x $width;

(my $broken = $orig) =~ s/(\S{$break_at})(?!\z)/$1 /g;

print qq{'$orig'\n}, qq{'$broken'\n};

[download]

Result:

'########'
'#### ####'

[download]

Update:

More ways to do it. With split:

my $broken = join( q{ }, grep { $_ ne q{} } split( qr/(\S{$broken_at})
+/, $orig ) );

[download]

With substr (ugh):

my $broken = $orig;
for my $chunk ( 1 .. length($broken) / $break_at ) {
    substr( $broken, $break_at * $chunk + $chunk - 1, 0 ,
            $break_at * $chunk + $chunk - 1 == length($broken) ? q{} :
+ q{ }
    );
}

[download]

-xdg

Code written by xdg and posted on PerlMonks is public domain. It is provided as is with no warranties, express or implied, of any kind. Posted code may not have been tested. Use of posted code is at your own risk.

In reply to Re^2: Breaking "long" lines of non-space-seperated characters by xdg
in thread Breaking "long" lines of non-space-seperated characters by skx

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