Update documentation.

HISTORY.md

@@ -6,10 +6,12 @@ History of SixtyPical
 
 *   Each table has a specified size now (although, bounds checking is not performed.)
 *   Initialized `byte table` values need not have all 256 bytes initialized.
-*   Constraints for `vector` type come immediately after the type, not the variable.
+*   Syntax for types has changed. `routine` (with constraints) is a type, while
-*   `vector table` storage, and ability to copy vectors in and out of same.
+    `vector` is now a type constructor (taking `routine`s only) and `table` is
+    also a type constructor.  This permits a new `vector table` type.
 *   Added `typedef`, allowing the user to define type aliases for readability.
 *   Added `define name routine {...}` syntax; `routine name {...}` is now legacy.
+*   Ability to copy vectors and routines into vector tables, and vectors out of same.
 *   Removed the evaluator.  The reference implementation only analyzes and compiles.
 *   Fixed bug where index register wasn't required to be initialized before table access.
 *   Fixed bug where trampolines for indirect calls weren't including a final `RTS`.

README.md

@@ -39,12 +39,6 @@ Documentation
 TODO
 ----
 
-### Demo game
-
-Finish the little demo "game" where you can move a block around the screen with
-the joystick (i.e. bring it up to par with the original demo game that was written
-for SixtyPical)
-
 ### `low` and `high` address operators
 
 To turn `word` type into `byte`.

doc/SixtyPical.md

@@ -15,20 +15,28 @@ the language.
 Types
 -----
 
-There are six *primitive types* in SixtyPical:
+There are five *primitive types* in SixtyPical:
 
 *   bit (2 possible values)
 *   byte (256 possible values)
 *   word (65536 possible values)
 *   routine (code stored somewhere in memory, read-only)
-*   vector (address of a routine)
 *   pointer (address of a byte in a buffer)
 
-There are also two *type constructors*:
+There are also three *type constructors*:
 
-*   T table (up to 256 entries, each holding a value of type T, where T is
+*   T table[N] (N is a power of 2, 1 ≤ N ≤ 256; each entry holds a value
-             either `byte` or `word`)
+                of type T, where T is `byte`, `word`, or `vector`)
 *   buffer[N] (N entries; each entry is a byte; N is a power of 2, ≤ 64K)
+*   vector T (address of a value of type T; T must be a routine type)
+
+### User-defined ###
+
+A program may define its own types using the `typedef` feature.  Typedefs
+must occur before everything else in the program.  A typedef takes a
+type expression and an identifier which has not previously been used in
+the program.  It associates that identifer with that type.  This is merely
+a type alias; two types with different names will compare as equal.
 
 Memory locations
 ----------------
@@ -111,11 +119,11 @@ and `trashes` lists like a routine (see below), and it may only hold addresses
 of routines which are compatible.  (Meaning, the routine's inputs (resp. outputs,
 trashes) must be a subset of the vector's inputs (resp. outputs, trashes.))
 
-    vector actor_logic
+    vector routine
              inputs a, score
              outputs x
              trashes y
-      @ $c000
+      actor_logic @ $c000
 
 Note that in the code of a routine, if a memory location is named by a
 user-defined symbol, it is an address in memory, and can be read and written.