util::always_false_type< typename > Struct Template Reference

A std::false_type with a template argument. More...

#include <MetaUtils.h>

Inheritance diagram for util::always_false_type< typename >:

Detailed Description

template<typename>
struct util::always_false_type< typename >

A std::false_type with a template argument.

See also

util::always_true_type, util::always_false_v

This type allows a static_assert to fail only when the template type it's in is being instantiated:

template <typename T>
struct MandatoryCustomizationPoint {
  static_assert(util::always_false_type<T>(), "You have to specialize!");
};

template <typename T>
struct MandatoryCustomizationPoint<std::vector<T>> {
  using type = typename std::vector<T>::reference;
};

In this example, using std::false_type instead of util::always_false_type might have tripped the compiler to trigger the assertion failure even if the class is not instantiated.

Definition at line 94 of file MetaUtils.h.

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The documentation for this struct was generated from the following file:

• larcorealg/larcorealg/CoreUtils/MetaUtils.h