A crude way of doing this without a module would be:

my $foo = '12345678901 23456789012345678901234567890123456789012345678
+901234567890123456789012345678901234567890';
                                                                      
+          
my $n = 15;
                                                                      
+          
my @chunks = ($foo =~ /(\S{0,$n})\s?/g);
                                                                      
+          
print join "\n",@chunks;
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/J\