Re: Class References

[Ali Çehreli]

On 11/20/2013 08:35 AM, Jeroen Bollen wrote:

I was more looking for a way to just access a type/class by specifying
an index... I don't really get your code.

TypeTuple can contain types. Do you know the index at compile time or at 
run time? Here is a program that demonstrates constructing an object for 
both of those cases:

module deneme;

import std.stdio;
import std.typetuple;
import std.string;

interface I
{}

class C1 : I
{}

class C2 : I
{}

// Question: Is there a way to determine the name of this module?
string moduleName = "deneme";
static const typeNames = [ "C1", "C2" ];

void makeWithCompileTimeIndex(size_t index)()
{
    alias typeList = TypeTuple!(C1, C2);

    alias Type = typeList[index];
    auto o = new Type();

    writefln("I made an object by using a compile-time index: %s", o);
}

void makeWithRunTimeIndex(size_t index)
{
    string fullTypeName = format("%s.%s", moduleName, typeNames[index]);
    auto o = cast(I)Object.factory(fullTypeName);
    writefln("I made an object by using a run-time index: %s", o);
}

void main()
{
    makeWithCompileTimeIndex!1();

    writefln("I can make an object of these types: %s", typeNames);
    write("Please enter the index of the type that you want: ");
    size_t index;
    readf(" %s", &index);
    makeWithRunTimeIndex(index);
}

Ali