Something like this: 
my $x = 'abc' x 10;
$x =~ s/(.{4})/$1 /sg;
print $x, "\n";
__END__
abca bcab cabc abca bcab cabc abca bc

[download]

If you only want to insert after word characters, you can use s/(\w{4})/$1 /g instead.

In reply to Re: How to split a string into chunks of length n or less by moritz
in thread How to split a string into chunks of length n or less by isync

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