Comment by pjmlp

We almost had it in OS/2, I guess many aren't aware that Smalltalk was kind of ".NET for OS/2" during its heyday.

Hence why it is a first party on SOM (OS/2 COM version), and SOM does support metaclasses.

But then OS/2 went as we all know, and with IBM's backing of Java, Visual Age products turned into Eclipse.

http://www.edm2.com/index.php/VisualAge_Smalltalk

https://en.wikipedia.org/wiki/IBM_System_Object_Model