On 21-06-2012 03:13, Jonathan M Davis wrote:
On Thursday, June 21, 2012 00:43:49 Namespace wrote:
That is my Code:
[code]
class Vector2D(T) {
private:
static Vector2D!(T) CastFromObject(Object o) {
import std.typetuple;
foreach (Type; TypeTuple!(byte, ubyte, short, ushort, int,
uint, long, ulong, float, double, real)) {
if (auto vec = cast(Vector2D!(Type)) o) {
return cast(Vector2D!(T)) vec;
}
}
return null;
}
public:
T x;
T y;
this(T x, T y) {
this.x = x;
this.y = y;
}
static Vector2D!(T) opCall(T x, T y) {
return new Vector2D!(T)(x, y);
}
float Summe() const pure nothrow {
return this.x + this.y;
}
override bool opEquals(Object o) const {
if (o is null) {
debug {
writeln("Object is null ;)");
}
return false;
}
const Vector2D!(T) vec = CastFromObject(o);
if (vec is this) {
return true;
}
return (vec.x == this.x)&& (vec.y == this.y);
}
override hash_t toHash() const pure nothrow {
return this.x + this.y;
}
override int opCmp(Object o) const {
if (o is null) {
return -1;
}
const Vector2D vec = CastFromObject(o);
if (vec is this) {
return 0;
}
if (this.Summe()> vec.Summe()) {
return 1;
}
if (this.Summe()< vec.Summe()) {
return -1;
}
return 0;
}
override string toString() const {
return "Vector2D!(" ~ T.stringof ~ ")(" ~ to!(string)(this.x) ~
", " ~ to!(string)(this.y) ~ ")";
}
}
[/code]
I have dmd 2.059 and with my current version of toHash i get the
compiler errors, that he cannot implicit convert from float,
real, double, long and so on to uint.
I cannot solve the problem with a simple cast or to!uint because
then he said that casts form float to uint are not allowed or
that to! isn't trusted and nothrow. I hate such annoying errors...
Eventually, toHash will have to be @safe const pure nothrow, but I don't think
that the compiler requires that yet (though work was being done on that, so it
may). You didn't mark toHash as @safe though, so it may be inferring it from
Object (I believe that it _has_ been changed so that attributes are now
inferred from the base class declarations when overriding). So, toHash may be
being inferred as @safe. Try marking toHash as @trusted. If that doesn't work,
then move its implementation into another function which you mark as @trusted
and have toHash call it (since @safe can call @trusted but can't do @system
stuff, unlike @trusted).
- Jonathan M Davis
It's actually @trusted as per the docs. I do not know why DMD infers
that to be @safe.....
In any case, the solution here is this:
override hash_t toHash() @trusted const pure nothrow {
return cast(hash_t)(this.x + this.y);
}
--
Alex Rønne Petersen
[email protected]
http://lycus.org
