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digitalmars.D.learn - smarter reflection issue

reply "Lloyd Dupont" <ld-REMOVE galador.net> writes:
I have a MemberDesc class which describe a class's members.
I fill it with a template method like that (with GETTER and SETTER some 
other templated method I wrote)
=====
MemberDesc MEMBER(T, string memberName)()
{
    TypeInfo ti = typeid( typeof(__traits(getMember, T, memberName)) );

    Variant function(Object target) getter = null;
    getter = &GETTER!(T, memberName);


    void function(Object target, Variant value) setter = null;
    setter = &SETTER!(T, memberName);

    return new MemberDesc(memberName, ti , getter, setter);
}
=====

And it works except that I don't do any check that the setter / getter 
method exist!

I tried something like that
====
static if( __traits(compiles, __traits(getMember, T, member)) )
{
    getter = &GETTER!(T, memberName);
}
====

but this always fail... mm.. how could I check for the getter?


and i guess it's even harder for the setter!
how about something like that (how to fix it?)
=====
static if( __traits(compiles, __traits(getMember, T, member) = 
typeof(__traits(getMember, T, memberName)).init) )
{
    setter = &SETTER!(T, memberName);
}
=====
Jun 16 2011
parent reply Jesse Phillips <jessekphillips+D gmail.com> writes:
MemberDesc MEMBER(T, string memberName)() if(std.traits.hasMember!(T,
memberName))
{
...
}

Lloyd Dupont Wrote:


 I have a MemberDesc class which describe a class's members.
 I fill it with a template method like that (with GETTER and SETTER some 
 other templated method I wrote)
 =====
 MemberDesc MEMBER(T, string memberName)()
 {
     TypeInfo ti = typeid( typeof(__traits(getMember, T, memberName)) );
 
     Variant function(Object target) getter = null;
     getter = &GETTER!(T, memberName);
 
 
     void function(Object target, Variant value) setter = null;
     setter = &SETTER!(T, memberName);
 
     return new MemberDesc(memberName, ti , getter, setter);
 }
 =====
 
 And it works except that I don't do any check that the setter / getter 
 method exist!
 
 I tried something like that
 ====
 static if( __traits(compiles, __traits(getMember, T, member)) )
 {
     getter = &GETTER!(T, memberName);
 }
 ====
 
 but this always fail... mm.. how could I check for the getter?
 
 
 and i guess it's even harder for the setter!
 how about something like that (how to fix it?)
 =====
 static if( __traits(compiles, __traits(getMember, T, member) = 
 typeof(__traits(getMember, T, memberName)).init) )
 {
     setter = &SETTER!(T, memberName);
 }
 =====
Jun 16 2011
parent "Lloyd Dupont" <ld-REMOVE galador.net> writes:
Hi Jesse, this won't work!
It's my fault in not explaining my problem well though...

I forget to mention something...
I'm using property syntax and try to call the method

Say I have
=====
private int _foo;
 property public int Foo() { return _foo; }
 property public void Foo(int value) { _foo = value; }
=====
if I call MEMBER(MyClass, "Foo")
I'd like to do some static test for "int Foo()" and "void Foo(int)"

So... how will I go on solving that?



"Jesse Phillips"  wrote in message news:itdqs4$mv0$1 digitalmars.com...

MemberDesc MEMBER(T, string memberName)() if(std.traits.hasMember!(T, 
memberName))
{
...
}

Lloyd Dupont Wrote:


 I have a MemberDesc class which describe a class's members.
 I fill it with a template method like that (with GETTER and SETTER some
 other templated method I wrote)
 =====
 MemberDesc MEMBER(T, string memberName)()
 {
     TypeInfo ti = typeid( typeof(__traits(getMember, T, memberName)) );

     Variant function(Object target) getter = null;
     getter = &GETTER!(T, memberName);


     void function(Object target, Variant value) setter = null;
     setter = &SETTER!(T, memberName);

     return new MemberDesc(memberName, ti , getter, setter);
 }
 =====

 And it works except that I don't do any check that the setter / getter
 method exist!

 I tried something like that
 ====
 static if( __traits(compiles, __traits(getMember, T, member)) )
 {
     getter = &GETTER!(T, memberName);
 }
 ====

 but this always fail... mm.. how could I check for the getter?


 and i guess it's even harder for the setter!
 how about something like that (how to fix it?)
 =====
 static if( __traits(compiles, __traits(getMember, T, member) =
 typeof(__traits(getMember, T, memberName)).init) )
 {
     setter = &SETTER!(T, memberName);
 }
 =====
Jun 16 2011