Spec and tests for initial values of locations.

README.markdown

@@ -44,7 +44,8 @@ TODO
 
 For 0.7:
 
-*   always analyze before executing or compiling, unless told not to
+*   initialized `byte` memory locations
+*   initialized `byte table` memory locations
 *   `word` type.
 *   `word table` type.
 
@@ -53,8 +54,13 @@ For 0.8:
 *   zero-page memory locations.
 *   indirect addressing.
 
+For 0.9
+
+*   save registers on stack or in memory (the preserves them = not trashed)
+
 At some point...
 
+*   always analyze before executing or compiling, unless told not to
 *   `trash` instruction.
 *   `interrupt` routines.
 *   6502-mnemonic aliases (`sec`, `clc`)
@@ -62,3 +68,5 @@ At some point...
 *   have `copy` instruction able to copy a constant to a user-def mem loc, etc.
 *   add absolute addressing in shl/shr, absolute-indexed for add, sub, etc.
 *   check and disallow recursion.
+*   automatic tail-call optimization (could be tricky, w/constraints?)
+*   re-order routines and optimize tail-calls to fallthroughs

doc/SixtyPical.md

@@ -1,7 +1,7 @@
 SixtyPical
 ==========
 
-This document describes the SixtyPical programming language version 0.6,
+This document describes the SixtyPical programming language version 0.7-PRE,
 both its execution aspect and its static analysis aspect (even though
 these are, technically speaking, separate concepts.)
 
@@ -79,10 +79,16 @@ name.
 
     byte pos
 
-A location in memory may be given explicitly on a user-defined memory location.
+An address in memory may be given explicitly on a user-defined memory location.
 
     byte table screen @ 1024
 
+Or, a user-defined memory location may be given an initial value.  But in this
+case, an explicit address in memory cannot be given.
+
+    byte pos = 0
+    byte table scores = [1, 3, 8, 17, 26, 100]
+
 A user-defined vector memory location is decorated with READS and WRITES 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)

tests/SixtyPical Syntax.md

@@ -123,7 +123,7 @@ Repeat with not
     | }
     = ok
 
-Extern memory locations
+Extern memory locations.
 
     | byte screen @ 1024
     | 
@@ -133,6 +133,16 @@ Extern memory locations
     | }
     = ok
 
+Initialized memory locations.
+
+    | byte lives = 3
+    | 
+    | routine main {
+    |   ld a, lives
+    |   st a, lives
+    | }
+    = ok
+
 Can't access an undeclared memory location.
 
     | routine main {