Re: Not able to load classes defined in archive file in Mac OSX using Object.factory
On Friday, 16 November 2018 at 14:55:52 UTC, Aditya wrote:
How can one write own factory function ? Any pointers to this ?
Something like
Interface delegate()[string] factories;
Interface create(string className) {
if(className in factories)
return factories[classname];
else
return null; // or throw if you prefer
}
In every module in which you create a class, you will want to add
code like this:
class Class : Interface {}
// register with the factory in a module constructor
static this() {
factories["Class"] = Interface delegate() {
return new Class();
}
}
And it should work.
Re: Not able to load classes defined in archive file in Mac OSX using Object.factory
On Friday, 16 November 2018 at 14:55:52 UTC, Aditya wrote:
On Friday, 16 November 2018 at 14:30:02 UTC, Adam D. Ruppe
wrote:
PS object.factory sucks and I hope it is removed some day.
There's no plan to do so, but I still wouldn't actually rely
on it... instead, I'd write your own factory function and
registration system, so you control it and will have
reliability to your specific needs.
but still if the factory works for you, eh, you can use it.
How can one write own factory function ? Any pointers to this ?
Thanx
for learning purpose you can make very simply a factory function
based on string comparison.
Object simpleFactory(string className)
{
import the_module_where_stuff_is_declared;
import the_module_where_thing_is_declared;
if (className == "Stuff")
return new Stuff;
else if if (className == "Thing")
return new Thing;
// and so on
else return null;
}
although this requires imports so the command line for building
should include more path using the "-I" cmd line switch.
I propose this solution because making a true factory might be
too complicated if you just start learning D.
Re: Not able to load classes defined in archive file in Mac OSX using Object.factory
On 11/16/18 9:51 AM, Aditya wrote:
On Friday, 16 November 2018 at 14:28:22 UTC, Adam D. Ruppe wrote:
On Friday, 16 November 2018 at 14:24:10 UTC, Aditya wrote:
./ss/Stat.d (defines interface named 'Stat')
./ss/Min.d (defines class named 'Min' that implements Stat)
Did you put a module declaration at the top of those files? Like
module ss.Stat;
That ought to be required; the compiler lets you skip it, but it
doesn't work reliably without it once you start importing the module
or other similar things.
But once you have that, the name of your class will be the full name
with module, so like if min has
module ss.Min;
class Min {}
the full class name will be
ss.Min.Min
the full module name dot the full class name.
Module Names were not added. But after adding the same, still same result.
// Following still doesn't work
ss.Min.Min
ss.ss.Min
ss.ss.Min.Min
stats.ss.Min.Min
stats.Min
So to let you know, Object.factory is not a maintained function. The
ability to instantiate classes based on the ModuleInfo was overruled by
the fact that we don't want to generate ModuleInfo if we don't have to,
and it should be as small as possible. Therefore, you need some triggers
to make sure the module info is included, and even then, I think, it's
not guaranteed to include the classinfo in that moduleinfo.
The better path is to use a registration system to add the desired
classes for reflection. Not a trivial thing, but that's probably the
path you want. I'd suggest looking at serialization libraries like
orange (http://code.dlang.org/packages/orange) or cereald
(http://code.dlang.org/packages/cerealed) for ideas, or maybe just use
one of them.
-Steve
Re: Not able to load classes defined in archive file in Mac OSX using Object.factory
On Friday, 16 November 2018 at 14:30:02 UTC, Adam D. Ruppe wrote: PS object.factory sucks and I hope it is removed some day. There's no plan to do so, but I still wouldn't actually rely on it... instead, I'd write your own factory function and registration system, so you control it and will have reliability to your specific needs. but still if the factory works for you, eh, you can use it. How can one write own factory function ? Any pointers to this ? Thanx
Re: Not able to load classes defined in archive file in Mac OSX using Object.factory
On Friday, 16 November 2018 at 14:28:22 UTC, Adam D. Ruppe wrote:
On Friday, 16 November 2018 at 14:24:10 UTC, Aditya wrote:
./ss/Stat.d (defines interface named 'Stat')
./ss/Min.d (defines class named 'Min' that implements Stat)
Did you put a module declaration at the top of those files? Like
module ss.Stat;
That ought to be required; the compiler lets you skip it, but
it doesn't work reliably without it once you start importing
the module or other similar things.
But once you have that, the name of your class will be the full
name with module, so like if min has
module ss.Min;
class Min {}
the full class name will be
ss.Min.Min
the full module name dot the full class name.
Module Names were not added. But after adding the same, still
same result.
// Following still doesn't work
ss.Min.Min
ss.ss.Min
ss.ss.Min.Min
stats.ss.Min.Min
stats.Min
Re: Not able to load classes defined in archive file in Mac OSX using Object.factory
PS object.factory sucks and I hope it is removed some day. There's no plan to do so, but I still wouldn't actually rely on it... instead, I'd write your own factory function and registration system, so you control it and will have reliability to your specific needs. but still if the factory works for you, eh, you can use it.
Re: Not able to load classes defined in archive file in Mac OSX using Object.factory
On Friday, 16 November 2018 at 14:24:10 UTC, Aditya wrote:
./ss/Stat.d (defines interface named 'Stat')
./ss/Min.d (defines class named 'Min' that implements Stat)
Did you put a module declaration at the top of those files? Like
module ss.Stat;
That ought to be required; the compiler lets you skip it, but it
doesn't work reliably without it once you start importing the
module or other similar things.
But once you have that, the name of your class will be the full
name with module, so like if min has
module ss.Min;
class Min {}
the full class name will be
ss.Min.Min
the full module name dot the full class name.
