import std.stdio;
version=PROBLEM;
interface I1 {
void foo();
}
interface IConsts {
}
version(PROBLEM){
interface I2 : IConsts, I1 {
void bar();
}
}
else{
interface I2 : I1, IConsts {
void bar();
}
}
class C1 : I1 {
void foo() { writefln("foo"); }
}
class C2 : C1, I2 {
void bar() { writefln("bar"); }
void bar2() { writefln("bar"); }
}
void main() {
C2 c2 = new C2();
c2.foo();
c2.bar();
}
//-------------------------------------
If version=PROBLEM is set, the error given is:
class t.C2 interface function I1.foo is not implemented
Comment #1 by 2korden — 2008-07-29T19:04:33Z
The following example has no workaround:
import std.stdio;
interface I1 {
void foo1();
}
interface I2 {
void foo2();
}
interface I3 : I1, I2 {
void bar();
}
class C1 : I1, I2 {
void foo1() { writefln("foo1"); }
void foo2() { writefln("foo2"); }
}
class C2 : C1, I3 {
void bar() { writefln("bar"); }
}
void main() {
C2 c2 = new C2();
c2.foo1();
c2.foo2();
c2.bar();
}
Comment #2 by 2korden — 2008-07-29T19:25:26Z
Just to make it more clear:
last example produces the following error message:
test.d(20): class test.C2 interface function I2.foo2 is not implemented
because of this line:
interface I3 : I1, I2 { /* ... */ }
I1 somehow shadows I2 and its implementation is not found in C2.
exchanging an interface declaration order:
interface I3 : I2, I1 { /* ... */ }
unhides I2 implementation but hides I1's one:
test.d(20): class test.C2 interface function I1.foo1 is not implemented.
Comment #3 by smjg — 2008-11-24T08:24:13Z
ISTM the bug is actually that the original code compiles without version=PROBLEM, rather than that it fails with.
http://www.digitalmars.com/d/1.0/interface.html
"A reimplemented interface must implement all the interface functions, it does not inherit them from a super class"
C2 reimplements I1, albeit indirectly. So the code should be
class C2 : C1, I2 {
void foo() { super.foo(); }
void bar() { writefln("bar"); }
void bar2() { writefln("bar"); }
}
You could argue that indirect reimplementation should be exempt from this requirement, but that would be an enhancement request.
Comment #4 by verylonglogin.reg — 2014-07-19T14:57:46Z
(In reply to Stewart Gordon from comment #3)
> ISTM the bug is actually that the original code compiles without
> version=PROBLEM, rather than that it fails with.
> [snip]
> "A reimplemented interface must implement all the interface functions, it
> does not inherit them from a super class"
> [snip]
So this code should NOT compile:
---
interface I1 { void f(); }
interface I2: I1 { }
class C1: I1 { void f() { } }
class C2: C1, I2 { } // fails for I1
---
Comment #5 by razvan.nitu1305 — 2019-09-09T14:34:24Z
This is the intended behavior. Closing as invalid.