Melasma Treatment and Hormones. Melasma is a condition that involves the discoloration of the skin usually on the face. Melasma is a result of too much exposure to sunlight. Melasma patches appear on the nose, lips, upper cheek, upper lip and the forehead. It mostly occurs in women than men. Genetic predisposition and hormonal imbalance plays a major role to determine if one will develop Melasma or not.
std::bind. std::bind is a Standard Function Objects that acts as a Functional Adaptor i.e. it takes a function as input and returns a new function Object as an output with with one or more of the arguments of passed function bound or rearranged.
(since C++11). Class template std::function is a general-purpose polymorphic function wrapper. Instances of std::function can store, copy, and invoke any Callable target -- functions, lambda expressions, bind expressions, or other function objects, as well as pointers to member functions and pointers to data members. The stored callable object is called the target of std::function. If a std::function contains no target, it is called empty. Invoking the target of an empty std::function results in std::bad_function_call exception being thrown. std::function satisfies the requirements of CopyConstructible and CopyAssignable.