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Front Page / Macros / Asserts / BOOST_MPL_ASSERT_MSG |
#define BOOST_MPL_ASSERT_MSG( condition, message, types ) \ unspecified token sequence \ /**/
Generates a compilation error with an embedded custom message when the condition doesn't hold.
#include <boost/mpl/assert.hpp>
Parameter | Requirement | Description |
---|---|---|
condition | An integral constant expression | A condition to be asserted. |
message | A legal identifier token | A custom message in a form of a legal C++ identifier token. |
types | A legal function parameter list | A parenthized list of types to be displayed in the error message. |
For any integral constant expression expr, legal C++ identifier message, and arbitrary types t1, t2,... tn:
BOOST_MPL_ASSERT_MSG( expr, message, (t1, t2,... tn) );
Return type: | None. |
---|---|
Precondition: | t1, t2,... tn are non-void. |
Semantics: | Generates a compilation error if expr::value != true, otherwise has no effect. When possible within the compiler's diagnostic capabilities, the error message will include the message identifier and the parenthized list of t1, t2,... tn types, and have a general form of: ... ************( ...::message )************)(t1, t2,... tn) ... |
BOOST_MPL_ASSERT_MSG( expr, message, (types<t1, t2,... tn>) );
Return type: | None. |
---|---|
Precondition: | None. |
Semantics: | Generates a compilation error if expr::value != true, otherwise has no effect. When possible within the compiler's diagnostics capabilities, the error message will include the message identifier and the list of t1, t2,... tn types, and have a general form of: ... ************( ...::message )************)(types<t1, t2,... tn>) ... |
template< typename T > struct my { // ... BOOST_MPL_ASSERT_MSG( is_integral<T>::value , NON_INTEGRAL_TYPES_ARE_NOT_ALLOWED , (T) ); }; my<void*> test; // In instantiation of `my<void*>': // instantiated from here // conversion from ` // mpl_::failed************(my<void*>:: // NON_INTEGRAL_TYPES_ARE_NOT_ALLOWED::************)(void*) // ' to non-scalar type `mpl_::assert<false>' requested