Perl 5.16 fc()

OlegG has asked for the wisdom of the Perl Monks concerning the following question:

Replies are listed 'Best First'.
Re: Perl 5.16 fc() by daxim (Curate) on May 22, 2012 at 10:39 UTC
First is false, second is true. `perl -Mutf8 -E'say lc(uc("\N{LATIN CAPITAL LETTER SHARP S}")) eq lc(uc("SS"))' perl -Mutf8 -E'say fc("\N{LATIN CAPITAL LETTER SHARP S}") eq fc("SS")'` [download]	[reply] [d/l]
Re^2: Perl 5.16 fc() by ikegami (Patriarch) on May 22, 2012 at 20:05 UTC
LATIN CAPITAL LETTER SHARP S uc("ẞ") ⇒ "ẞ" (LATIN CAPITAL LETTER SHARP S) lc("ẞ") ⇒ "ß" (LATIN SMALL LETTER SHARP S) fc("ẞ") ⇒ "ss" LATIN SMALL LETTER SHARP S uc("ß") ⇒ "SS" ← lc("ß") ⇒ "ß" (LATIN SMALL LETTER SHARP S) fc("ß") ⇒ "ss" uc("SS") ⇒ "SS" lc("SS") ⇒ "ss" fc("SS") ⇒ "ss" uc("ss") ⇒ "SS" lc("ss") ⇒ "ss" fc("ss") ⇒ "ss" If you reverse the `uc` and the `lc`, the two expressions will be equivalent for this example, but I don't know if it holds for all cases, and it's not something you should count on.	[reply] [d/l] [select]
Re^2: Perl 5.16 fc() by OlegG (Monk) on May 22, 2012 at 11:00 UTC
Really, thanks	[reply]
Re: Perl 5.16 fc() by moritz (Cardinal) on May 22, 2012 at 09:41 UTC
I don't know if it's true, but if I were trying to construct counter examples, I'd experiment with these special cases. Perl 6 - the future is here, just unevenly distributed	[reply]
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