On 11/12/13 3:05 PM, Jakob Ovrum wrote:
On Tuesday, 12 November 2013 at 22:36:22 UTC, Timon Gehr wrote:
- Every class in any imported module will need to show up in the
generated code even if it is never used unless global static analysis
is carried out on arguments to Object.factory.
- If I know the fully qualified name of a class, there are better ways
to instantiate this class than passing a string containing that name
to Object.factory in order to call the default constructor.
- The functionality provided by Object.factory is trivially replaced
by a solution more specifically tailored to the problem at hand using
compile-time reflection.
+ 1.
To test, I made a Factory template that works like this:
---
unittest
{
import std.traits : fullyQualifiedName;
interface I {}
class A : I {}
class B : I {}
alias f = Factory!(I, A, B);
Stopped reading here, and everybody should. There is a thorough
treatment of object factories in "Modern C++ Design" which I recommend
not because I wrote it, but because it's thorough. Part of it is to show
why the approach above is marred by dependency issues and should often
be avoided.
Andrei
