How to check for implicit type conversion WITHOUT checking the source object's interface
I'm trying to find a way to see if a given object is convertible to
std::string, but with certain restrictions. Normally, is_convertible<> would
be fine, but in this case it doesn't work for my needs.
Here's the situation in more detail. I've got a class Foo with a string
conversion operator:
class Foo { public: operator std::string () const; };
I want some kind of is_convertible
At 08:49 2005-06-15, Stephen Gross wrote:
I'm trying to find a way to see if a given object is convertible to std::string, but with certain restrictions. Normally, is_convertible<> would be fine, but in this case it doesn't work for my needs.
Here's the situation in more detail. I've got a class Foo with a string conversion operator:
class Foo { public: operator std::string () const; };
I want some kind of is_convertible
to return FALSE, but something like is_convertible to return TRUE. Basically, I want is_convertible to check to see if the target type (std::string) has an implicit constructor taking the input type; I *don't* want is_convertible to check to see if the input type has a conversion-to-target-type function.
the difference between them being? (I don't mean implementation here, I mean "meaning").
Is there a way to do this?
--Steve _______________________________________________ Boost-users mailing list Boost-users@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users
Victor A. Wagner Jr. http://rudbek.com The five most dangerous words in the English language: "There oughta be a law"
I'm trying to find a way to see if a given object is convertible to std::string, but with certain restrictions. Normally, is_convertible<> would be fine, but in this case it doesn't work for my needs.
Here's the situation in more detail. I've got a class Foo with a string conversion operator:
class Foo { public: operator std::string () const; };
I want some kind of is_convertible
to return FALSE, but something like is_convertible to return TRUE. Basically, I want is_convertible to check to see if the target type (std::string) has an implicit constructor taking the input type; I *don't* want is_convertible to check to see if the input type has a conversion-to-target-type function. Is there a way to do this?
Yes, it's quite cunning and we use it to implement is_enum: a conversion
sequence is only permitted one user defined conversion, so try:
is_convertible
participants (3)
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John Maddock
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Stephen Gross
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Victor A. Wagner Jr.