I'd like to point out that despite the character error in Skeeve's post ("\x2022" is a space (!) followed by "22", oops), his report is for real. 
$latin = "\xa0";               # nbsp
$unicode= $latin . pack 'U0';  # convert to UTF-8

print "Latin 1: ", $latin =~  /\s/ ? "yes":"no", "\n";
print "Unicode: ", $unicode =~/\s/ ? "yes":"no", "\n";

[download]
result: 
Latin 1: no
Unicode: yes

In reply to Re: inconsistency in whitespace handling by bart
in thread inconsistency in whitespace handling by Skeeve

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