opaque

[abdallahijazi]

Dear all,

Would anyone kindly explain to me what does "opaque" mean? here is the context:
"This memory is not directly accessible to the user, and objects stored there are opaque."

Thanks in advance

[Incubbus]

I guess it has to do with some system objects...

opaque means, that the user is not able to interact with the objects - because he does not know about his existence - directly... which is the same as the first sentence :D...

[abdallahijazi]

ok thx Incubbus

[jsmith]

Opaque in the programming sense means not viewable or not usable.

Example:

class Foo {
    struct Boolean { int dummy_; };  // Opaque type -- it is private, so user of Foo cannot "see" this type

    int x;

  public:
    // Implementation of the "safebool" idiom
    operator Boolean::int*() const
       { return x ? &Boolean::dummy_ : 0; }
};

[abdallahijazi]

thx Smith,