How can I use structs in a named enum?
.. That is enum E : Struct {}
struct S {
int a;
}
// ok
enum E : S {
a = S(1),
}
// Error: need member function opCmp() for struct S to compare
/*
enum E2 : S {
a = S(1),
b = S(2)
}
*/
struct S2 {
int a;
int opCmp(ref const S2 other)
{
return a == other.a ? 0 : (a other.a ? -1 : 1);
}
}
// Error: function opcmp.S2.opCmp (ref const(S2) other) is not callable
using argument types (E3)
// Error: cast(const(S2))S2(1) is not an lvalue
// Error: function opcmp.S2.opCmp (ref const(S2) other) is not callable
using argument types (E3)
// Error: cast(const(S2))S2(1) is not an lvalue
enum E3 : S2 {
a = S2(1),
b = S2(2)
}
void main() {
}
So E3 is passed as the parameter to S2.opCmp..?
Re: How can I use structs in a named enum?
On Wed, 29 Feb 2012 12:27:32 +0100, simendsjo simend...@gmail.com wrote:
On Wed, 29 Feb 2012 12:15:35 +0100, simendsjo simend...@gmail.com
wrote:
.. That is enum E : Struct {}
struct S {
int a;
}
// ok
enum E : S {
a = S(1),
}
// Error: need member function opCmp() for struct S to compare
/*
enum E2 : S {
a = S(1),
b = S(2)
}
*/
struct S2 {
int a;
int opCmp(ref const S2 other)
{
return a == other.a ? 0 : (a other.a ? -1 : 1);
}
}
// Error: function opcmp.S2.opCmp (ref const(S2) other) is not callable
using argument types (E3)
// Error: cast(const(S2))S2(1) is not an lvalue
// Error: function opcmp.S2.opCmp (ref const(S2) other) is not callable
using argument types (E3)
// Error: cast(const(S2))S2(1) is not an lvalue
enum E3 : S2 {
a = S2(1),
b = S2(2)
}
void main() {
}
So E3 is passed as the parameter to S2.opCmp..?
Hmm.. By removing ref const in opCmp, it works as expected
Btw.. Removing the ref is obvious, but why do I have to remove const?
Perhaps also the documentation for opCmp should be improved..?
Re: How can I use structs in a named enum?
simendsjo: Perhaps also the documentation for opCmp should be improved..? Also, and maybe here DMD has to give better error messages :-) Bye, bearophile
Re: How can I use structs in a named enum?
On Wed, 29 Feb 2012 13:40:51 +0100, bearophile bearophileh...@lycos.com wrote: simendsjo: Perhaps also the documentation for opCmp should be improved..? Also, and maybe here DMD has to give better error messages :-) Bye, bearophile Yes. Using argument types E3 doesn't make much sense when the named enum is a complex type.
Re: How can I use structs in a named enum?
simendsjo: Yes. Using argument types E3 doesn't make much sense when the named enum is a complex type. If this diagnostic bug/enhancement is not in Bugzilla then I suggest you to add it. Now there are two persons that are quite efficient at fixing Bugzilla bugs, but they need to know there is a problem. Bye, bearophile
Re: How can I use structs in a named enum?
On Wednesday, February 29, 2012 12:15:35 simendsjo wrote:
.. That is enum E : Struct {}
struct S {
int a;
}
// ok
enum E : S {
a = S(1),
}
// Error: need member function opCmp() for struct S to compare
/*
enum E2 : S {
a = S(1),
b = S(2)
}
*/
struct S2 {
int a;
int opCmp(ref const S2 other)
{
return a == other.a ? 0 : (a other.a ? -1 : 1);
}
}
// Error: function opcmp.S2.opCmp (ref const(S2) other) is not callable
using argument types (E3)
// Error: cast(const(S2))S2(1) is not an lvalue
// Error: function opcmp.S2.opCmp (ref const(S2) other) is not callable
using argument types (E3)
// Error: cast(const(S2))S2(1) is not an lvalue
enum E3 : S2 {
a = S2(1),
b = S2(2)
}
void main() {
}
So E3 is passed as the parameter to S2.opCmp..?
http://d.puremagic.com/issues/show_bug.cgi?id=4423
- Jonathan M Davis
Re: How can I use structs in a named enum?
On Wed, 29 Feb 2012 19:00:10 +0100, bearophile bearophileh...@lycos.com wrote: simendsjo: Yes. Using argument types E3 doesn't make much sense when the named enum is a complex type. If this diagnostic bug/enhancement is not in Bugzilla then I suggest you to add it. Now there are two persons that are quite efficient at fixing Bugzilla bugs, but they need to know there is a problem. Bye, bearophile http://d.puremagic.com/issues/show_bug.cgi?id=7612
