分かち書きしないっぽい文字を表す正規表現（User-Defined Character Properties）

spacing.pl

#!/usr/bin/env perl
use strict;
use warnings;
use utf8;
use 5.010;

binmode STDOUT, ":utf8";

my $text = "これはpenです";
$text =~ s/(\p{IsNonSpacingCharacter})([^\p{IsNonSpacingCharacter}])/$1 $2/g;
$text =~ s/([^\p{IsNonSpacingCharacter}])(\p{IsNonSpacingCharacter})/$1 $2/g;

say $text; # これは pen です

sub IsNonSpacingCharacter {
    return <<'END';
+utf8::Hiragana
+utf8::Katakana
+utf8::InKatakana
+utf8::Han
+utf8::InCJKSymbolsAndPunctuation
+utf8::InHalfwidthAndFullwidthForms
END
}