misc/kforth: Start command processing.

doc/index.rst

@@ -10,6 +10,7 @@ Contents:
    part-0x02
    part-0x03
    part-0x04
+   part-0x05
 
 Indices and tables
 ==================

doc/part-0x05.rst

@@ -0,0 +1,46 @@
+Write You a Forth, 0x05
+-----------------------
+
+:date: 2018-02-24 12:23
+:tags: wyaf, forth
+
+Today I need to start actually doing things with tokens. This requires two
+things:
+
+1. Some idea of what a word is, and
+2. A dictionary of words
+
+I started taking some notes on this previously, and I think there are a few
+kinds of words that are possible:
+
+1. Numbers (e.g. defining a variable)
+2. Built-in functions
+3. Lambda functions (that is, user-defined functions).
+
+Stage 1 really only needs to incorporate #2, so that's what I'll focus on for
+now. However, to prepare for the future, I'm going to define a ``Word`` base
+class and inherit from there. This interface is going to need to be
+stack-aware, so what I've done is define a ``System`` struct in ``system.h``::
+
+        #ifndef __KF_CORE_H__
+        #define __KF_CORE_H__
+        
+        #include "defs.h"
+        #include "stack.h"
+        
+        typedef struct _System {
+                Stack<KF_INT>        dstack;
+        } System;
+        
+        
+        #endif // __KF_CORE_H__
+
+This will let me later add in support for the return stack and other things
+that might be useful. Other ideas: adding something like an ``errno``
+equivalent to indicate the last error, and storing a dictionary of words. This
+will need some restructuring, though. Anyways, this works for now.
+
+The Word interface
+^^^^^^^^^^^^^^^^^^
+
+Now I can start defining a Word.h.