A14-7-1 - Unofficial Autosar C++ Guidelines Reference

Rule A14-7-1 (required, implementation, automated)

A type used as a template argument shall provide all members that are used by the template.

Rationale

If a type used as a template argument does not provide all the members used by the template, the instantiation of the template will result in an ill-formed program. It is not clear for developer whether the template should be used with the type.

Example

// $Id: A14-7-1.cpp 289436 2017-10-04 10:45:23Z michal.szczepankiewicz $
#include <cstdint>
class A
{
public:
void SetProperty(std::int32_t x) noexcept { property = x; }
void DoSomething() noexcept {}

private:
std::int32_t property;
};
struct B
{
};
class C
{
public:
void DoSomething() noexcept {}
};
template <typename T>
class D
{
public:
void F1() {}
void F2()
{
T t;

t.SetProperty(0);
}
void F3()
{
T t;
t.DoSomething();
}
};

void Fn() noexcept
{
D<A> d1; // Compliant - struct A provides all needed members
d1.F1();
d1.F2();
d1.F3();

D<B> d2; // Non-compliant - struct B does not provide needed members
d2.F1();
// d2.f2(); // Compilation error - no ’property’ in struct B
// d2.f3(); // Compilation error - no member named ’doSomething’ in struct
// B

D<C> d3; // Non-compliant - struct C does not provide property
d3.F1();
// d3.F2(); // Compilation error - no property in struct C
d3.F3();
}

Unofficial Autosar C++ Guidelines Reference

Rationale

Example

See also