Re: do { quit; } else { }

On 08/04/2025 22:18, Tim Rentsch wrote:

bart <bc@freeuk.com> writes:
 

On 08/04/2025 18:32, Tim Rentsch wrote:
>

bart <bc@freeuk.com> writes:
>

On 08/04/2025 15:50, David Brown wrote:
>

On 08/04/2025 13:35, bart wrote:
>

But this need not be the case.  For example this is module A:
>
--------------------------
   #include <stdio.h>
>
   typedef struct point {float a; float b;} Point;
>
   float dist(Point);
>
   int main(void) {
   Point p = {3, 4};
   printf("%f\n", dist(p));
   }
--------------------------
>
And this is module B that defines 'dist':
>
>
--------------------------
   #include <math.h>
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   typedef float length;
   typedef struct _tag {length x, y;} vector;
>
   length dist(vector p) {return sqrt(p.x*p.x + p.y*p.y);}
--------------------------
>
The types involved are somewhat different, but are compatible
enough for it to work.

>
The two types are entirely compatible.

>
Are they?

>
No, they are not.  The type names 'Point' and 'vector' name two
distinct types, and those types are not compatible, because
the two struct tags are different.
>
Because the two types are not compatible, even just calling the
function dist() is undefined behavior.

>
I get an incompatible error (from the example you snipped) even when I
remove both struct tags.
>
I can't use the same struct tag in the same scope as one will clash
with the other.  But if I have the second in an inner scope, then I
again get the error.

 If you want to make a point or ask a question about C code,
SHOW THE CODE.  And show all of it.  Don't make people guess
by showing only some of the code or by giving just a description.

I'm showing the code but you keep snipping it!  If you want testable code, just wrap it with 'int main() { ... }'. (I assumed you could figure that out.)
Here I was responding to your remark that the types are incompatible because the struct tags are different. If by that you mean 'struct X' vs 'struct Y', then I said that isn't the case, as my example without such tags showed.