What's the tilde in a &= ~b ?

[Benjamin B.]

Hi everyone,

in this thing I inherited there's a statement like this:

a &= ~b;

where a is an int and b has been declared this way:

const b = 0x0002;

and thus is probably an int as well.

My question: What's the tilde doing there? Is that standard C++? What
does it mean?

Cheers &= thanks
Benjamin

[Howard]

"Thomas Tutone" <Th***********@ yahoo.com> wrote in message
news:11******** **************@ u72g2000cwu.goo glegroups.com.. .

Howard wrote:

>> (You really should get yourself a good C++ book, by
>> the way.)
>
> Uhm possible ... though I'll rather concentrate on the standard library
> and the likes if I have the choice ...
>

You lost me there. What do you mean by the "standard library"? The
"standard template library" [STL]? The STL is a set of templates,
written
in C++. If you're referring to the C++ run-time library, then you're
talking about a given compiler vendor's implementation of the C++
language
features (such as I/O, basic math functions, etc.). Perhaps you're
talking
about some on-line Help system in your compiler's IDE?

Have you really not heard of the C++ standard library? If not, perhaps
you need to follow your own good advice and get yourself a good book as
well. I highly recommend Josuttis' The C++ Standard Library. Or
perhaps I misunderstood you (I seem to do that at times).

I see your point. My book (The C++ Programming Language", Stroustrup),
refers to the "standard library", but it's kind of talking about everything
in the C++ language, including the STL. (In fact, in answering his own
question: "what should be in the standard library?", he answers:
"everything !".) So really, saying the "standard library" doesn't mean all
that much, does it? Mostly people talk about the STL, otherwise they're
really just talking about the language as a whole, right?

And anyway, my point was really: what about using the "standard library"
negates needing a book to study it? The OP was saying he'd "rather
concentrate on the standard library..." when I suggested getting a C++ book,
as if one precluded the other. That statement is really what made no sense
to me.

-Howard

[Rolf Magnus]

Howard wrote:

You lost me there. What do you mean by the "standard library"? The
"standard template library" [STL]? The STL is a set of templates,
written in C++. If you're referring to the C++ run-time library, then
you're talking about a given compiler vendor's implementation of the C++
language features (such as I/O, basic math functions, etc.). Perhaps
you're talking about some on-line Help system in your compiler's IDE?
Have you really not heard of the C++ standard library? If not, perhaps
you need to follow your own good advice and get yourself a good book as
well. I highly recommend Josuttis' The C++ Standard Library. Or
perhaps I misunderstood you (I seem to do that at times).

I see your point. My book (The C++ Programming Language", Stroustrup),
refers to the "standard library", but it's kind of talking about
everything in the C++ language, including the STL.

Maybe by "STL" you do mean the standard library, because the C++ standard
library is AFAIK based on the STL to a great degree.
(In fact, in answering his own question: "what should be in the standard
library?", he answers: "everything !".) So really, saying the "standard
library" doesn't mean all that much, does it?
Well, what should be and what is in the standard library are two different
things.
Mostly people talk about the STL, otherwise they're really just talking
about the language as a whole, right?
If people here talk about "the standard library", they usually mean the
library that is part of standard C++, i.e. defined in the C++ standard.
And anyway, my point was really: what about using the "standard library"
negates needing a book to study it? The OP was saying he'd "rather
concentrate on the standard library..." when I suggested getting a C++
book, as if one precluded the other. That statement is really what made
no sense to me.

Right. It doesn't make much sense to get all the details about the C++
standard library without even knowing the basics about the C++ syntax.

[Mike Smith]

Benjamin B. wrote:

Howard wrote:

(You really should get yourself a good C++ book, by
the way.)

Uhm possible ... though I'll rather concentrate on the standard library
and the likes if I have the choice ...

You still need to learn the *language*.

--
Mike Smith