std::source_location::function_name

 

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std::source_location

Member functions

Creation

source_location::source_location

source_location::current

Field access

source_location::line

source_location::column

source_location::file_name

source_location::function_name

 

constexprconstchar* function_name()constnoexcept;		(since C++20)

Returns the name of the function associated with the position represented by this object, if any.

Parameters

(none)

Return value

If this object represents a position in a body of a function, returns an implementation-defined null-terminated byte string corresponding to the name of the function.

Otherwise, an empty string is returned.

Example

std::source_location::function_name may help to obtain the names of functions (including the special functions) alongside with their signatures.

Run this code

#include <cstdio>#include <utility>#include <source_location>   inlinevoid print_function_name(conststd::source_location& location = std::source_location::current()){std::puts(location.function_name());// prints the name of the caller}   void foo(double&&){ print_function_name();}   namespace bar {void baz(){ print_function_name();}}   template<typename T>auto pub(T){ print_function_name();return42;}   struct S { S(){ print_function_name();} S(int){ print_function_name();} ~S(){ print_function_name();} S& operator=(S const&){ print_function_name();return*this;} S& operator=(S&&){ print_function_name();return*this;}};   int main(int, charconst*const[]){ print_function_name(); foo(3.14); bar::baz(); pub(0xFULL); S p; S q{42}; p = q; p = std::move(q);[]{ print_function_name();}();}

Possible output:

int main(int, const char* const*) void foo(double&&) void bar::baz() auto pub(T) [with T = long long unsigned int] S::S() S::S(int) S& S::operator=(const S&) S& S::operator=(S&&) main(int, const char* const*)::<lambda()> S::~S() S::~S()

See also

line	return the line number represented by this object (public member function)
column	return the column number represented by this object (public member function)
file_name	return the file name represented by this object (public member function)