Boost.Hana  1.6.0
Your standard library for metaprogramming
Assertions

Description

Macros to perform different kinds of assertions.

Macros

#define BOOST_HANA_RUNTIME_ASSERT(condition)   unspecified
 Expands to a runtime assertion. More...
 
#define BOOST_HANA_RUNTIME_ASSERT_MSG(condition, message)   unspecified
 Equivalent to BOOST_HANA_RUNTIME_ASSERT, but allows providing a custom failure message. More...
 
#define BOOST_HANA_CONSTANT_ASSERT(condition)   unspecified
 Compile-time assertion for Constants. More...
 
#define BOOST_HANA_CONSTANT_ASSERT_MSG(condition, message)   unspecified
 Equivalent to BOOST_HANA_CONSTANT_ASSERT, but allows providing a custom failure message. More...
 
#define BOOST_HANA_ASSERT(condition)   unspecified
 Expands to the strongest form of assertion possible for the given condition. More...
 
#define BOOST_HANA_ASSERT_MSG(condition, message)   unspecified
 Equivalent to BOOST_HANA_ASSERT, but allows providing a custom failure message. More...
 
#define BOOST_HANA_CONSTEXPR_ASSERT(condition)   unspecified
 Expands to a static assertion or a runtime assertion, depending on whether constexpr lambdas are supported. More...
 
#define BOOST_HANA_CONSTEXPR_ASSERT_MSG(condition, message)   unspecified
 Equivalent to BOOST_HANA_CONSTEXPR_ASSERT, but allows providing a custom failure message.
 
#define BOOST_HANA_RUNTIME_CHECK_MSG(condition, message)
 Equivalent to BOOST_HANA_RUNTIME_ASSERT_MSG, but not influenced by the BOOST_HANA_CONFIG_DISABLE_ASSERTIONS config macro. For internal use only.
 
#define BOOST_HANA_RUNTIME_CHECK(...)
 Equivalent to BOOST_HANA_RUNTIME_ASSERT, but not influenced by the BOOST_HANA_CONFIG_DISABLE_ASSERTIONS config macro. For internal use only.
 
#define BOOST_HANA_CONSTANT_CHECK_MSG(condition, message)
 Equivalent to BOOST_HANA_CONSTANT_ASSERT_MSG, but not influenced by the BOOST_HANA_CONFIG_DISABLE_ASSERTIONS config macro. For internal use only.
 
#define BOOST_HANA_CONSTANT_CHECK(...)
 Equivalent to BOOST_HANA_CONSTANT_ASSERT, but not influenced by the BOOST_HANA_CONFIG_DISABLE_ASSERTIONS config macro. For internal use only.
 
#define BOOST_HANA_CHECK_MSG(condition, message)
 Equivalent to BOOST_HANA_ASSERT_MSG, but not influenced by the BOOST_HANA_CONFIG_DISABLE_ASSERTIONS config macro. For internal use only.
 
#define BOOST_HANA_CHECK(...)
 Equivalent to BOOST_HANA__ASSERT, but not influenced by the BOOST_HANA_CONFIG_DISABLE_ASSERTIONS config macro. For internal use only.
 
#define BOOST_HANA_CONSTEXPR_CHECK_MSG(condition, message)   implementation-defined
 Equivalent to BOOST_HANA_CONSTEXPR_ASSERT_MSG, but not influenced by the BOOST_HANA_CONFIG_DISABLE_ASSERTIONS config macro. For internal use only.
 
#define BOOST_HANA_CONSTEXPR_CHECK(...)   implementation-defined
 Equivalent to BOOST_HANA_CONSTEXPR_ASSERT, but not influenced by the BOOST_HANA_CONFIG_DISABLE_ASSERTIONS config macro. For internal use only.
 

Macro Definition Documentation

◆ BOOST_HANA_RUNTIME_ASSERT

#define BOOST_HANA_RUNTIME_ASSERT (   condition)    unspecified

#include <boost/hana/assert.hpp>

Expands to a runtime assertion.

Given a condition known at runtime, this macro expands to a runtime assertion similar to the assert macro. The provided condition must be explicitly convertible to a bool, and it must not be a model of the Constant concept. If the condition is a Constant, a static assertion will be triggered, asking you to use the BOOST_HANA_CONSTANT_ASSERT macro instead.

Note
This macro may only be used at function scope.

◆ BOOST_HANA_RUNTIME_ASSERT_MSG

#define BOOST_HANA_RUNTIME_ASSERT_MSG (   condition,
  message 
)    unspecified

#include <boost/hana/assert.hpp>

Equivalent to BOOST_HANA_RUNTIME_ASSERT, but allows providing a custom failure message.

Warning
Conditions that contain multiple comma-separated elements should be parenthesized.

◆ BOOST_HANA_CONSTANT_ASSERT

#define BOOST_HANA_CONSTANT_ASSERT (   condition)    unspecified

#include <boost/hana/assert.hpp>

Compile-time assertion for Constants.

Given a condition known at compile-time in the form of a Constant, this macro expands to a compile-time assertion similar to a static_assert. The provided condition must be a model of the Constant concept, in which case its value is retrieved using hana::value and then converted to a bool. If the condition is not a Constant, a static assertion will be triggered, asking you to use the BOOST_HANA_RUNTIME_ASSERT macro instead.

This macro may be used at global/namespace scope and function scope only; it may not be used at class scope. Note that the condition may never be evaluated at runtime. Hence, any side effect may not take place (but you shouldn't rely on side effects inside assertions anyway).

◆ BOOST_HANA_CONSTANT_ASSERT_MSG

#define BOOST_HANA_CONSTANT_ASSERT_MSG (   condition,
  message 
)    unspecified

#include <boost/hana/assert.hpp>

Equivalent to BOOST_HANA_CONSTANT_ASSERT, but allows providing a custom failure message.

Warning
Conditions that contain multiple comma-separated elements should be parenthesized.

◆ BOOST_HANA_ASSERT

#define BOOST_HANA_ASSERT (   condition)    unspecified

#include <boost/hana/assert.hpp>

Expands to the strongest form of assertion possible for the given condition.

Given a condition, BOOST_HANA_ASSERT expands either to a compile-time or to a runtime assertion, depending on whether the value of the condition is known at compile-time or at runtime. Compile-time assertions are always preferred over runtime assertions. If the condition is a model of the Constant concept, its value (retrievable with hana::value) is assumed to be explicitly convertible to bool, and a compile-time assertion is performed on it. Otherwise, the condition itself is assumed to be explicitly convertible to bool, and a runtime assertion is performed on it.

If the assertion can be carried out at compile-time, the condition is not guaranteed to be evaluated at runtime at all (but it may). Hence, in general, you shouldn't rely on side effects that take place inside an assertion.

Note
This macro may only be used at function scope.

◆ BOOST_HANA_ASSERT_MSG

#define BOOST_HANA_ASSERT_MSG (   condition,
  message 
)    unspecified

#include <boost/hana/assert.hpp>

Equivalent to BOOST_HANA_ASSERT, but allows providing a custom failure message.

Warning
Conditions that contain multiple comma-separated elements should be parenthesized.

◆ BOOST_HANA_CONSTEXPR_ASSERT

#define BOOST_HANA_CONSTEXPR_ASSERT (   condition)    unspecified

#include <boost/hana/assert.hpp>

Expands to a static assertion or a runtime assertion, depending on whether constexpr lambdas are supported.

This macro is used to assert on a condition that would be a constant expression if constexpr lambdas were supported. Right now, constexpr lambdas are not supported, and this is always a runtime assertion. Specifically, this is equivalent to BOOST_HANA_RUNTIME_ASSERT.