Object Common understanding of ”object” ” Object” in programming - represents real-life or abstract objects - is a generalized variable (structure) - is a being defined and used according to syntactic and semantic rules of the programming language Structure - set of data elements, usually of ...
Operators for accessing class members dot ” . ” object.variable; // just like in a C structure object.method(); // encapsulation scope operator ” :: ” class::variable; // sizeof, static variables class::method(); // defining methods, static methods Scope definition (object. and class::) usual...
Prototypes of fun ctions Function prototypes are required!!! (return value, name, arguments) In C: a prototype int f() is assumed, in C++ not #include ”foo_prototypes.h” void foo(); … foo(); … void foo() {}; ...
References reference to type T: T& it is a pointer that looks like a variable int i=7, // variable int & iref=i; // reference must be initialized // i.e. associated with something (i) iref++; // now i==8 may be misleading avoid funct...
Structures and classes Initialization in braces { } is valid only for classes: - whose all fields are public - that have no explicit constructor struct s_xy { int x, y; }; s_xy sxy={10,20}; // ok //s_xy sxy1(10,10) - bad! struct xy { int x,y; x...
The default constructor If no constructors were declared, the compiler generates a default constructor It is a constructor with no arguments, of an empty body, for the T class: T::T() { } If we declare any constructor (even constructor with args) then compiler does not generate the default co...
This exists in every non-static method a pointer to the object, for which the method was called used for returning reference or pointer to the object for which the method was called does not occupy
Type void * no automatic conversion to other pointer types void *malloc(size_t size); char *str; int *pi; str = (char *) malloc(10); pi = (int *)malloc(100); automatic conversion from almost any pointer type (exception: const *, volatile *) vo...
Unions In C++ a union is a class, but: - It cannot contain objects with constructors or destructors defined - There can be no access restrictions - all the fields are public - It cannot inherit from a class ...
Why to inherit? class person { char * name, * surname; public: void print_name (); void print_surname(); void print_all(); } class adult { char * name, * surname, * ID_card; public: void print_name(); void print_surname(); void print_ID_card(); void print_all(); } class person { char * name, * surn...
