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[Bug 3716] Editorial: clarify that none is subtype of all types

From: <bugzilla@wiggum.w3.org>
Date: Tue, 19 Sep 2006 10:53:51 +0000
To: public-qt-comments@w3.org
Message-Id: <E1GPdEd-00054t-97@wiggum.w3.org>


frans.englich@telia.com changed:

           What    |Removed                     |Added
OtherBugsDependingO|3675                        |
              nThis|                            |
           Keywords|                            |editorial
            Summary|Only fn:error() as operand  |Editorial: clarify that none
                   |                            |is subtype of all types

------- Comment #1 from frans.englich@telia.com  2006-09-19 10:53 -------
Jerome clarified this in #3675:

"The type 'none' is a subtype of every type. See subtyping Section 8.3.2-- t1
is a subtype of t2 iff every value v, v matches t1 implies v matches t2. Since
no value matches 'none', none <: t for every t."

Tim suggests the editorial change that:

"Might it be worth spelling that out for clarity in the notes of
section 8.3.2?"
Received on Tuesday, 19 September 2006 10:54:11 UTC

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