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A emi(qualification transformation) adds ti(const) or ti(volatile)
qualifications to em(pointers). This transformation is applied when the
function template's type parameter explicitly specifies tt(const) (or
tt(volatile)) but the function's argument isn't a tt(const) or tt(volatile)
entity. In that case tt(const) or tt(volatile) is provided by the compiler.
Subsequently the compiler deduces the template's type parameter. For example:
verb( template<typename Type>
Type negate(Type const &value)
{
return -value;
}
int main()
{
int x = 5;
x = negate(x);
})
Here we see the function template's tt(Type const &value) parameter: a
reference to a tt(const Type). However, the argument isn't a tt(const int),
but an tt(int) that can be modified. Applying a qualification transformation,
the compiler adds tt(const) to tt(x)'s type, and so it matches tt(int const
x). This is then matched against tt(Type const &value) allowing the compiler
to deduce that tt(Type) must be tt(int).
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