private selective import + overload = breaks accessibility rules

[H. S. Teoh]

On Tue, Jan 16, 2018 at 06:13:27PM +0000, rumbu via Digitalmars-d-learn wrote:
> module a;
> 
> private import std.math: isNaN;
> 
> //custom overload
> public bool isNaN(int i) { return false; }
> 
> 
> =============================
> 
> module b;
> import a;
> 
> void foo()
> {
>     bool b = isNaN(float.nan);
>     //compiles successfully calling std.math.isNaN even it should not be
> visible.
> }
> 
> Is this normal behavior or a bug?

Which version of the compiler is this?  I'm pretty sure the
std.math.isNaN imported by module a should not be visible in module b.
The latest compiler should emit a deprecation warning for this.

Of course, it's possible that having a public symbol in module a that
overloads an imported symbol may have triggered a buggy corner case in
the compiler.  If so, a bug should be filed.


> OK, let's try another:
> 
> module b;
> import a;
> import std.math; // <== note this
> 
> void foo()
> {
>     bool b = isNaN(float.nan);
> }
> 
> It ends in a very funny error message:
> 
> Error: std.math.isNaN!float.isNaN at src\phobos\std\math.d(5335) conflicts
> with std.math.isNaN!float.isNaN at src\phobos\std\math.d(5335)
[...]

LOL!  Yeah, if this is the latest compiler, it's definitely a bug.


T

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