# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1373223961 -7200
# Node ID ed96a883b4b14a127795c87eaffc163c2253811f
# Parent  0402f18ff296dbfd8fa3627b5b6bdc37ab7adabb
Simplified the selection of special functions used in generated syspython code.
Added some notes about low-level syspython special functions.
Added a reminder to the assignment documentation.

diff -r 0402f18ff296 -r ed96a883b4b1 docs/assignment.txt
--- a/docs/assignment.txt	Fri Jul 05 23:13:22 2013 +0200
+++ b/docs/assignment.txt	Sun Jul 07 21:06:01 2013 +0200
@@ -43,6 +43,9 @@
   unless attribute usage observations are employed to detect possible attribute
   assignments
 
+  Remember that once a function is assigned to a class, it will have that class
+  as context (as an unbound method)
+
 Access types:
 
   Access to stored value from...    Effect on context   Optimised instruction     Unoptimised instruction
diff -r 0402f18ff296 -r ed96a883b4b1 docs/syspython.txt
--- a/docs/syspython.txt	Fri Jul 05 23:13:22 2013 +0200
+++ b/docs/syspython.txt	Sun Jul 07 21:06:01 2013 +0200
@@ -23,6 +23,27 @@
 or method. Note that the apply function resembles the Python function of the
 same name but is not actually that particular function.
 
+Low-Level Code
+--------------
+
+Most Python-level program code should be wrapped in special function
+invocations, and as a result other syntax features might be used to express
+low-level concepts. Low-level operations may also be expressed using other
+special functions. For example:
+
+    storelocal(element, loadobjtable(loadattr(obj, classcode), attrcode))
+
+Here, element holds the raw data provided by the table access involving a base
+defined by the classcode of an object and an offset defined by the supplied
+attrcode.
+
+Note that all low-level functions deal only with addresses and offsets, not
+symbols. In the above example, loadattr combines the address of obj with the
+symbol classcode whose actual value must be substituted by the compiler.
+However, the loadobjtable function requires a genuine offset value for the
+classcode (which is why loadattr is being used to obtain it), and a genuine
+offset for the attrcode (which is provided directly).
+
 Program Data and Data Structure Definition
 ------------------------------------------
 
diff -r 0402f18ff296 -r ed96a883b4b1 micropython/syspython.py
--- a/micropython/syspython.py	Fri Jul 05 23:13:22 2013 +0200
+++ b/micropython/syspython.py	Sun Jul 07 21:06:01 2013 +0200
@@ -52,10 +52,10 @@
 # Some of the assignment operations cannot be supported unless attribute usage
 # observations are being made.
 
-assattr_functions = ("storeaddress", "storeaddresscontext", "storeaddresscontext",
-                     "storeattr", "storeattrindex", None)
-getattr_functions = ("loadaddress", "loadaddresscontext", "loadaddresscontextcond",
-                     "loadattr", "loadattrindex", "loadattrindexcontextcond")
+assattr_functions = ("storeattrcontext", "storeattrcontext",
+                     "storeattr", "storeattrindexcontextcond")
+getattr_functions = ("loadattrcontext", "loadattrcontextcond",
+                     "loadattr", "loadattrindexcontextcond")
 
 # Source code classes.
 
@@ -518,8 +518,8 @@
 
         # Choose the appropriate special functions.
 
-        (opaddress, opaddresscontext, opaddresscontextcond,
-            opattr, opattrindex, opattrindexcontextcond) = expr and assattr_functions or getattr_functions
+        (opattrcontext, opattrcontextcond, opattr, opattrindexcontextcond) = \
+            expr and assattr_functions or getattr_functions
 
         accessor = self.dispatch(node.expr)
 
@@ -536,11 +536,11 @@
 
             if node._access_type == "static":
                 if node._set_context == "set":
-                    op = opaddresscontext
+                    op = opattrcontext
                 elif node._set_context == "cond":
-                    op = opaddresscontextcond
+                    op = opattrcontextcond
                 else:
-                    op = opaddress
+                    op = opattr
 
                 parent = self._generateValue(node._attr_deduced.parent)