Why connot declare a static member of STRUCT or UNION?

[arkmancn]

Any comments? thanks.

Jim

[Ian Collins]

ar******@gmail. com wrote:

Any comments? thanks.

Please put your question in the body of your post and don't SHOUT.

C isn't C++.

--
Ian Collins.

[Jack Klein]

On Mon, 22 Oct 2007 18:14:08 -0700, ar******@gmail. com wrote in
comp.lang.c:

Any comments? thanks.

Because there is no such thing as STRUCT or UNION in C.

--
Jack Klein
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[Walter Roberson]

In article <11************ **********@k35g 2000prh.googleg roups.com>,
<ar******@gmail .comwrote:

>Any comments? thanks.

What would you expect it to mean? That, in the case of a struct,
that the rest of the struct would lose its values when the struct
went out of scope, but the static member would not? That, in
the case of a union, that... that what? That if you had last written
to it via the static member that the value would be remembered
but that it wouldn't be remembered if you had written to the
union via one of the non-static members ???
--
"History is a pile of debris" -- Laurie Anderson

[Road Tang]

ar******@gmail. com wrote:

Any comments? thanks.

Jim

In Standard C, it can't.
because C doesn't support it. C isn't a language that supports
OO programming favor.

You can use C++, and post in comp.lang.c++ .

>

-Road.
--
C FAQ: http://c-faq.com/

[santosh]

ar******@gmail. com wrote:

Any comments? thanks.

Note that C is case sensitive. STRUCT and UNION are not defined by the C
Standard, you probably meant struct and union.

As for your question, a struct or union is an aggregate type. That means
all it's member objects have the same scope. Though the static
qualifier can apply to the whole structure, it's application to one of
it's members makes very little sense; and I see little point in it too.

[James Kuyper Jr.]

ar******@gmail. com wrote:

Any comments? thanks.

The keyword 'static' has many meanings in C, none of which make sense
inside a struct. C++ gave that keyword an additional meaning, which
applies only in that context, but this newsgroup is for discussing C,
not C++.

[Richard]

"James Kuyper Jr." <ja*********@ve rizon.netwrites :

ar******@gmail. com wrote:

>Any comments? thanks.

The keyword 'static' has many meanings in C, none of which make sense
inside a struct. C++ gave that keyword an additional meaning, which
applies only in that context, but this newsgroup is for discussing C,
not C++.

It would make perfect sense to see static in a struct as far as I can
see. What is so nonsensical about it? Or is your point not that it
wouldn't make sense, but that it's simply not available?

[James Kuyper Jr.]

Richard wrote:

"James Kuyper Jr." <ja*********@ve rizon.netwrites :

>ar******@gmail. com wrote:

>>Any comments? thanks.

The keyword 'static' has many meanings in C, none of which make sense
inside a struct. C++ gave that keyword an additional meaning, which
applies only in that context, but this newsgroup is for discussing C,
not C++.

It would make perfect sense to see static in a struct as far as I can
see. What is so nonsensical about it? Or is your point not that it
wouldn't make sense, but that it's simply not available?

The standard defines (at least) three different meanings for the keyword
static, depending upon whether it's at file scope, block scope, or
function prototype scope. A single struct type, once defined, could be
used to declare an object in any of those scopes, so the possible
meaning of the 'static' keyword when applied to a member would have to
change with the scope.

File scope: what would it mean for a structure object to have external
linkage, but a member of that object to have internal linkage (or vice
versa)?

Block scope: What would it mean for a structure object to be
automatically or dynamically allocated, and to have a member that was
statically allocated (or vice versa)?

Function prototype scope: the only meaning currently provided for static
in this scope is that it requires that the leading dimension of an array
passed as a specific argument to the function to be at least as long as
the length specified for the corresponding parameter. I don't see how
that could be applied to struct members.

I'm not saying that answers couldn't be invented for these questions;
I'm merely saying that any answer would be a new invention, not a simple
extension to the currently defined meanings of 'static'.

[santosh]

James Kuyper Jr. wrote:

Richard wrote:

>It would make perfect sense to see static in a struct as far as I can
see. What is so nonsensical about it? Or is your point not that it
wouldn't make sense, but that it's simply not available?

The standard defines (at least) three different meanings for the
keyword static, depending upon whether it's at file scope, block
scope, or function prototype scope. A single struct type, once
defined, could be used to declare an object in any of those scopes, so
the possible meaning of the 'static' keyword when applied to a member
would have to change with the scope.

File scope: what would it mean for a structure object to have external
linkage, but a member of that object to have internal linkage (or vice
versa)?

Presumably that the static member is invisible to other modules?

Block scope: What would it mean for a structure object to be
automatically or dynamically allocated, and to have a member that was
statically allocated (or vice versa)?

Presumably that the static member retains it's previous value?

<snip>