On May 1, 2006, at 2:56 AM, Bernd Dorn wrote:
On 01.05.2006, at 01:55, Stephan Richter wrote:
On Sunday 30 April 2006 19:34, Bernd Dorn wrote:
component.queryMultiAdapter((bar,baz), IFoo) is not None or False
this way you always get True or False
ok, for this case it is ok
but when you have a class that uses __conform__ None may be
returned when you use this
or am i wrong?
It might return None, which according to our semantics means that the
adaptation failed. Since None has a False meaning in a boolean
context, Stephan's version will work out. However...
Why not just:
component.queryMultiAdapter((bar,baz), IFoo, default=False)
...this assumes that the adapter evaluates to a boolean True, which
is not generically (reliably) the case. As a pattern, Bernd's
version is safer, although the trailing "or False" is superfluous.
component.queryMultiAdapter((bar,baz), IFoo) is not None
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