From: Peter Dimov (pdimov_at_[hidden])
Date: 2004-11-18 08:18:29
Vladimir Prus wrote:
> Peter Dimov wrote:
>>> The very same question arises with path/wpath:
>>> path p( "foo")
>>> p /= wpath(L"bar");
>> We can avoid it by not defining a mixed operator/=, though.
> Yes, but what if I need to do this? Then there should be some
> conversion function, and why that conversion function can't be called
> by mixed operator/=, then?
Because the library may not convert the way you want it to. Even if a wpath
is convertible to a path, the converting constructor should probably be
p /= wpath(L"bar");
seems fine at first sight, but it's actually an error; it should have been
p /= "bar";
Without an implicit conversion,
p /= path(wpath(L"bar"));
the redundant conversions are much more evident.
And to get back to the original question, p always stores a narrow path, so
there is no ambiguity whether L"bar" needs to be narrowed, or "foo" is to be
widened. There is a potential ambiguity with a mixed operator/, though, if
one is provided. Which is why there shouldn't be a mixed operator/. ;-)
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