http://d.puremagic.com/issues/show_bug.cgi?id=8161

           Summary: -property should give an error for invalid property
                    functions
           Product: D
           Version: unspecified
          Platform: All
        OS/Version: All
            Status: NEW
          Severity: enhancement
          Priority: P2
         Component: DMD
        AssignedTo: nobody@puremagic.com
        ReportedBy: jmdavisProg@gmx.com


--- Comment #0 from Jonathan M Davis <jmdavisProg@gmx.com> 2012-05-29 22:36:00 PDT ---
This code compiles with -property:

struct S
{
    @property void prop()
    {
    }
}

void main()
{
}


It makes no sense that it would. prop returns nothing, so it can't be used as a getter, and it takes nothing, so it can't be used as a setter. Neither

S s;
auto a = s.prop;

nor

s.prop = a;

would compile, so there's no point in letting prop compile with @property. Another example would be a function like

struct S
{
    @property void prop(int a, int b)
    {
    }
}

It can't possibly be used as a property function either. I'd argue that any such function should be considered an error as long as it's marked as @property and the -property flag is used.

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------

http://d.puremagic.com/issues/show_bug.cgi?id=8161



--- Comment #1 from Kenji Hara <k.hara.pg@gmail.com> 2012-05-29 23:24:13 PDT ---
(In reply to comment #0)
> This code compiles with -property:
> 
> struct S
> {
>     @property void prop()
>     {
>     }
> }
> 
> void main()
> {
> }
> 
> 
> It makes no sense that it would.

I can agree.

> Another example would be a function like
> 
> struct S
> {
>     @property void prop(int a, int b)
>     {
>     }
> }
> 
> It can't possibly be used as a property function either. I'd argue that any such function should be considered an error as long as it's marked as @property and the -property flag is used.

A @property function has two parameters is now allowed for UFCS property setter.

@property foo(T)(T obj, int val) { ... }
void main() {
   S s;
   s.foo = 1;  // translated to .foo(s, 1), it's valid.
}

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------

http://d.puremagic.com/issues/show_bug.cgi?id=8161



--- Comment #2 from Jonathan M Davis <jmdavisProg@gmx.com> 2012-05-29 23:30:30 PDT ---
> A @property function has two parameters is now allowed for UFCS property setter.

> @property foo(T)(T obj, int val) { ... }
> void main() {
>    S s;
>    s.foo = 1;  // translated to .foo(s, 1), it's valid.
> }

Yeah, because that's a free function. It's valid to use it as a property, so it makes sense for it to compile with @property. The example that I gave with two arguments was a member function, which already has the invisible this parameter, so it won't work as a property.

The point is that any function which cannot be legally used as a property function should not compile when marked with @property and compiled with -property.

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------

http://d.puremagic.com/issues/show_bug.cgi?id=8161



--- Comment #3 from Kenji Hara <k.hara.pg@gmail.com> 2012-05-29 23:38:53 PDT ---
(In reply to comment #2)
> > A @property function has two parameters is now allowed for UFCS property setter.
> 
> > @property foo(T)(T obj, int val) { ... }
> > void main() {
> >    S s;
> >    s.foo = 1;  // translated to .foo(s, 1), it's valid.
> > }
> 
> Yeah, because that's a free function. It's valid to use it as a property, so it makes sense for it to compile with @property. The example that I gave with two arguments was a member function, which already has the invisible this parameter, so it won't work as a property.
> 
> The point is that any function which cannot be legally used as a property function should not compile when marked with @property and compiled with -property.

OK. I got an understanding.

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------