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/C++std::bad_function_call
Defined in header <functional> | ||
|---|---|---|
class bad_function_call; | (since C++11) |
std::bad_function_call is the type of the exception thrown by std::function::operator() if the function wrapper has no target.
Inheritance diagram.
Member functions
| (constructor) | constructs a new bad_function_call object (public member function) |
| operator= | replaces the bad_function_call object (public member function) |
| what | returns the explanatory string (public member function) |
std::bad_function_call::bad_function_call
bad_function_call() noexcept; | (1) | (since C++11) |
bad_function_call( const bad_function_call& other ) noexcept; | (2) | (since C++11) |
Constructs a new bad_function_call object with an implementation-defined null-terminated byte string which is accessible through what().
*this and other both have dynamic type std::bad_function_call then std::strcmp(what(), other.what()) == 0.Parameters
| other | - | another exception object to copy |
std::bad_function_call::operator=
bad_function_call& operator=( const bad_function_call& other ) noexcept; | (since C++11) |
Assigns the contents with those of other. If *this and other both have dynamic type std::bad_function_call then std::strcmp(what(), other.what()) == 0 after assignment.
Parameters
| other | - | another exception object to assign with |
Return value
*this.
std::bad_function_call::what
virtual const char* what() const noexcept; | (since C++11) |
Returns the explanatory string.
Parameters
(none).
Return value
Pointer to a null-terminated string with explanatory information. The string is suitable for conversion and display as a std::wstring. The pointer is guaranteed to be valid at least until the exception object from which it is obtained is destroyed, or until a non-const member function (e.g. copy assignment operator) on the exception object is called.
Notes
Implementations are allowed but not required to override what().
Inherited from std::exception
Member functions
|
[virtual] | destroys the exception object (virtual public member function of std::exception) |
|
[virtual] | returns an explanatory string (virtual public member function of std::exception) |
Example
#include <functional>
#include <iostream>
int main()
{
std::function<int()> f = nullptr;
try
{
f();
}
catch(const std::bad_function_call& e)
{
std::cout << e.what() << '\n';
}
}Possible output:
bad function call
See also
|
(C++11) | wraps callable object of any copy constructible type with specified function call signature (class template) |
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