Sun May 31 15:39:24 CEST 2009

Simpler DTC

The 14-bit VM is clever, but it's not simple.  It might be used for
something else later.  The fact that the return stack is executable
code might lead to somewhere.  However, the 14-bit constants are a
pain and the extra effort to make tail recursion work is not worth it.

Right now what is important is to get the self-hosted Forth to work
and make it reasonably portable.

Let's go back to a simple threaded Forth.  I'm not sure what the name
is for the method I'm using: it's direct threading[1] with primitives
that do not use NEXT, but instead use an explicit interpreter
loop. (NEXT = procedure return).

[1] http://en.wikipedia.org/wiki/Threaded_code#Direct_threading