The simple assignment operator has the following form:
lvalue = expr
The operator stores the value of the right operand expr in the object designated by the left operand lvalue.
The left operand must be a modifiable lvalue. The type of an assignment operation is the type of the left operand.
If the left operand is not a class type, the right operand is implicitly converted to the type of the left operand. This converted type will not be qualified by const or volatile.
If the left operand is a class type, that type must be complete. The copy assignment operator of the left operand will be called.
If the left operand is an object of reference type, the compiler will assign the value of the right operand to the object denoted by the reference.