opCast problem with 2.060
Namespace
rswhite4 at googlemail.com
Wed Jul 25 05:59:15 PDT 2012
[code]
import std.conv : to;
class Vector2D(T) {
public:
T x, y;
this(T x, T y) {
this.x = x;
this.y = y;
}
U opCast(U)() const {
return new U(x, y);
}
}
alias Vector2D!(short) Vector2s;
alias Vector2D!(float) Vector2f;
void main() {
Vector2s vs1 = new Vector2s(42, 23);
Vector2s vs2 = new Vector2s(42, 23);
assert(vs1 == vs2);
}
[/code]
prints:
dmd -w -O -property -unittest -debug -of"vec_test_2060"
"vec_test_2060.d" (im Verzeichnis: D:\D\D_Scripts\Test 4)
vec_test_2060.d(13): Error: no constructor for Object
vec_test_2060.d(24): Error: template instance
vec_test_2060.Vector2D!(short).Vector2D.opCast!(Object) error
instantiating
Kompilierung fehlgeschlagen.
And this code:
[code]
import std.conv : to;
class Vector2D(T) {
public:
T x, y;
this(T x, T y) {
this.x = x;
this.y = y;
}
U opCast(U : inout(Vector2D!V), V)() const {
return new U(x, y);
}
}
alias Vector2D!(short) Vector2s;
alias Vector2D!(float) Vector2f;
void main() {
Vector2s vs1 = new Vector2s(42, 23);
Vector2s vs2 = new Vector2s(42, 23);
assert(vs1 == vs2);
}
[/code]
prints:
dmd -w -O -property -unittest -debug -of"vec_test_2060"
"vec_test_2060.d" (im Verzeichnis: D:\D\D_Scripts\Test 4)
vec_test_2060.d(24): Error: template instance opCast!(Object)
opCast!(Object) does not match template declaration opCast(U :
inout(Vector2D!(V)),V)
vec_test_2060.d(24): Error: function expected before (), not
vs1.opCast!(Object) of type void
vec_test_2060.d(24): Error: template instance opCast!(Object)
opCast!(Object) does not match template declaration opCast(U :
inout(Vector2D!(V)),V)
vec_test_2060.d(24): Error: function expected before (), not
vs2.opCast!(Object) of type void
Kompilierung fehlgeschlagen.
If i add to the last code this:
[code]
const(U) opCast(U = typeof(this))() const {
return this;
}
[/code]
I get:
dmd -w -O -property -unittest -debug -of"vec_test_2060"
"vec_test_2060.d" (im Verzeichnis: D:\D\D_Scripts\Test 4)
vec_test_2060.d(28): Error: cannot implicitly convert expression
(vs1.opCast()) of type const(Object) to object.Object
vec_test_2060.d(28): Error: cannot implicitly convert expression
(vs2.opCast()) of type const(Object) to object.Object
Kompilierung fehlgeschlagen.
With 2.059 both works fine. What is the problem now?
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