class - How to create a dynamically allocated C++ Object and its pointer? -


this might newbie question, asking myself anyway.

if have object class defined:

object *p = new object();

does code create pointer p, , @ location p, place object object, correct?

this means:

  • prepare variable address parent class , name p
  • allocate enough memory store contents of parent class
  • call constructor of parent class
  • store address of memory in variable p.

edit: in response comment:

this not way construct class. other 1 allocate class statically, eg.

parent p;

in such case don't store pointer parent class in variable p, whole class itself. in such case:

  • memory class located on stack in frame reserved function, defines variable (stack allocated once, when program loaded memory)
  • constructor called automatically, when program reaches point of declaration of variable.
  • destructor called automatically, when program leaves scope of variable
  • no memory deallocated (at least none instance of parent class), because stack reused later.

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