On 08/20/2018 10:57 PM, Jonathan M Davis wrote:
Runtime reflection is theoretically possible in D, but it requires generating the appropriate stuff for every type involved so that the runtime stuff has something to work with. Java built all of that into the language and has the JVM to boot, which fundamentally changes some of what can be done. With D, we're basically in exactly the same boat as C or C++ except that we have better compile-time type introspection. In principle, a runtime reflection facility could be built using that, but even if it were part of Phobos, it would still have to be opt-in. So, I don't know how useful such a solution would ever be outside of very specific use cases. Regardless, given that D's object files, linking, etc. are using the C tools, it was never going to be the case that Java-style runtime reflection would be built in to D like it is with Java.
Yea. Not to disagree at all with those reasons, but that is unfortunate. I've long been interested in how various features of D (not exclusively D, though) combine in ways that, in effect, obsolete much of traditional OOP inheritence-based polymorphism - offering the same abilities of OOP but without many of the notable downsides. Java-style runtime reflection would take us that much further in this regard. (Plus, it would make D that much more of a universal-toolbox of a language.) Oh well, dreams vs reality ;)
