Consider the following code:
template <class T>
void f(T, int) {}
template <class T>
void f(int, T) {}
template<>
void f(int, int) {} // ambiguous ?
My compiler complains that the last definition is an "ambiguous template
specialization `f<>' for `void f(int, int)' ". I have tested this on a
few compilers and all they complain there. What is wrong in this
specialization ? Consider similar code:
template <class T, class C>
void f(int, T, C) {}
template <class T, class C>
void f(T, int, C) {}
template<class C>
void f(int, int, C) {}
Compiler does not complain that 3rd function is ambiguous. Why ? What is
the difference ?
Rafal
--
sed -e s/s/a/g <my_address >my_right_addre ss
1  2464 
Rafal Dabrowa wrote in news:co******** **@news.onet.pl in comp.lang.c++: Consider the following code:
template <class T>
void f(T, int) {}
template <class T>
void f(int, T) {}
template<>
void f(int, int) {} // ambiguous ?
My compiler complains that the last definition is an "ambiguous
template
specialization `f<>' for `void f(int, int)' ". I have tested this on a
few compilers and all they complain there. What is wrong in this
specialization ? Consider similar code:
template <class T, class C>
void f(int, T, C) {}
template <class T, class C>
void f(T, int, C) {}
template<class C>
void f(int, int, C) {}
Compiler does not complain that 3rd function is ambiguous. Why ? What
is the difference ?
The diffrence is that in the second example you aren't
specializing anything, you are just providing an overload
that happens to be a template.
In the first example the explicit specialization f<>(int, int)
could be a specialization of either of the two overloads that
preceded it, hence the ambiguity.
HTH.
--
sed -e s/s/a/g <my_address >my_right_addre ss
Rob.
-- http://www.victim-prime.dsl.pipex.com/ This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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