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digitalmars.D - Having problems using __traits

reply Daniel Ribeiro Maciel <danielmaciel gmail.com> writes:
Hello! I'm currently having this issue using __traits. Can anyone tell me what
am I doing wrong, or whether this is a compiler bug or not?
Thanks!

Source code is attached to this message.

S:\Repositorios\tpp\trunk\script.d(15): Error: string expected as second
argument of __traits getMember instead of method
S:\Repositorios\tpp\trunk\script.d(15): Error: function expected before (), not
false of type bool
S:\Repositorios\tpp\trunk\script.d(24): Error: template instance
script.exportType!(Test).exportType.methodHandler!(Test,method) error
instantiating
S:\Repositorios\tpp\trunk\script.d(30):        instantiated from here:
exportType!(Test)

Best Regards,
Daniel
Apr 03 2010
parent reply bearophile <bearophileHUGS lycos.com> writes:
Daniel Ribeiro Maciel:


 Hello! I'm currently having this issue using __traits. Can anyone tell me what
am I doing wrong, or whether this is a compiler bug or not?<


At the moment DMD2 has holes likes Swiss cheese. You have hit one, two, or more
than two different bugs. This is the first bug:


struct Test {
	void hello() {}
}
void main() {
    Test t;
    string m = "hello";
    __traits(getMember, t, m)();
}


The error message is wrong: if m must be an enum/immutable string, then the
error message has to say so.
The second problem can be seen here:


import std.c.stdio: puts;

class Test {
	void hello() {
        puts("hello!");
    }
}

void methodHandler(T, alias member)() {
    auto o = new T();
    __traits(getMember, o, member)();
}

void main() {
    auto methods = __traits(allMembers, Test);
    foreach (method; methods)
        if (method == "hello")
            methodHandler!(Test, "hello")();
}


If you replace "hello" inside methodHandler!(Test, "hello")();  with  method,
the program doesn't compile. I don't know if it's the same problem as before.
I can put in bugzilla the first bug.

Bye,
bearophile
Apr 03 2010
parent bearophile <bearophileHUGS lycos.com> writes:
The first is now bug 4058. The second I don't know if it's the same bug...

Bye,
bearophile
Apr 03 2010