What does the * do with that class?

Question

It might be a "dumb" question but i dont know what * do in that code.

ClassA* classa;

ClassA is a class, so what does the * actually do with a class? and how this ?operator? called?

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score 1 · Accepted Answer · answered Jun 10 '15 at 12:37

* does not do anything with a class, it changes the type of the declared variable by making it a pointer:

ClassA *classa; // classa is a pointer to ClassA

You can add multiple asterisks to make pointers to pointers, pointers to pointers to pointers, and so on:

ClassA **classa; // classa is a pointer to pointer to ClassA
ClassA ***classa; // classa is a pointer to pointer to pointer to ClassA

Note that when the same asterisk is used in an expression (as opposed to a declaration) it "reduces" the level of a pointer, so

ClassA *classa;
foo(*classa); // Dereferences the pointer, producing ClassA

dasblinkenlight! Thanks for your answer, now i got it! – user1888798 Jun 10 '15 at 12:44 — user1888798, Jun 10 '15 at 12:44

score 0 · Answer 2 · answered Jun 10 '15 at 12:36

0

Pointer declaration.

After this declaration, classa is a variable with type "Pointer-to-a-ClassA object". It can point to any ClassA object, or any object that inherits from ClassA

answered Jun 10 '15 at 12:36

abelenky

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What does the * do with that class?

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