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tordek | 15 years ago

As said elsewhere: "Declaration follows use".

    int *foo;
means "foo is a pointer to int". But that's explained different from how it's written. More clearly, you can say that "foo" is an int. Then, doing

    int *foo;
    foo = 50;
is obviously wrong because "foo" is not an int; however

    int *foo;
    *foo = 50;
is correct.

Similarly for arrays:

    int *foo[50];
means "foo is an array of pointers to int", or "
foo[5] is an int".

From there follows that & is the antithesis of , and they negate each other:

    int *foo; //foo is a pointer to int.
    &*foo; //the address of the contents of foo
    foo; // same as above, but shorter.

discuss

order

ewjordan|15 years ago

Sorry, that didn't make much sense to me - in your first example, you can't say "foo is an int", because it's not, it's a pointer to an int. And in your last example, you can't say "foo[5] is an int", because it's not, it's a pointer to int.

In response to the original question, I think the answer is that

  int *foo;
is a common way of writing it because that's the way the compiler resolves it. As mentioned elsewhere,

  int* foo, bar;
is equivalent to

  int *foo; int bar
so treating the star as part of the type can cause problems.

But I agree fully - it makes a lot more sense to me to consider the pointer star as a flag on the type, not a modifier to the name. Just one of the many warts on C and C++ that make me happy I have to use them so infrequently...

[Edit: formatting, stars were getting swallowed when put inline]

lmkg|15 years ago

> [Edit: formatting, stars were getting swallowed when put inline]

The same thing happened to the post you're responding to, and that's why it's not making sense to you. The author really meant to say star-foo and star-foo[5], but instead italicized a bunch of text in between.