# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1336947596 -7200
# Node ID 6e530bfa326eb6cdd002f843100771774e0db41f
# Parent  8bf8faf18dbe169fa81b7bbe4c9849fe7d00f956
Improved support for specific type annotations in program regions.

diff -r 8bf8faf18dbe -r 6e530bfa326e TO_DO.txt
--- a/TO_DO.txt	Fri May 11 00:20:56 2012 +0200
+++ b/TO_DO.txt	Mon May 14 00:19:56 2012 +0200
@@ -126,7 +126,11 @@
 -----------------------
 
 Consider handling CallFunc in micropython.inspect in order to produce instances of specific classes.
-Then, consider adding support for guard removal/verification where known instances are involved.
+Then, consider adding support for guard removal/verification where known instances are involved. For
+example:
+
+  l = []
+  l.append(123) # type deductions are filtered using instantiation knowledge
 
 Frame Optimisations
 ===================
diff -r 8bf8faf18dbe -r 6e530bfa326e micropython/common.py
--- a/micropython/common.py	Fri May 11 00:20:56 2012 +0200
+++ b/micropython/common.py	Mon May 14 00:19:56 2012 +0200
@@ -88,6 +88,9 @@
         if not self.has_key(obj):
             self[obj] = set()
 
+    def issubset(self, other):
+        return set(self).issubset(other)
+
     # Dictionary and related methods.
 
     def __getitem__(self, key):
@@ -170,6 +173,9 @@
 
     for old_dict in dicts:
         for key, value in old_dict.items():
+
+            # Add existing mappings within an object set.
+
             if not new_dict.has_key(key):
                 if value is not None:
                     new_dict[key] = ObjectSet(value)
diff -r 8bf8faf18dbe -r 6e530bfa326e micropython/data.py
--- a/micropython/data.py	Fri May 11 00:20:56 2012 +0200
+++ b/micropython/data.py	Mon May 14 00:19:56 2012 +0200
@@ -441,9 +441,26 @@
 
         if not hasattr(node, "_attrspecifictypes"):
             merged = {}
-            for user in node._attrdefs:
-                merged.update(user._attrnames)
-            node._attrmerged = combine_mapping_dicts(deepen_mapping_dict(node._attrnames), deepen_mapping_dict(merged))
+
+            # Get the combined usage information from the user definitions.
+
+            for user in node._attrdefs or [node]:
+
+                # Filter the usage for each name using the local usage
+                # information.
+
+                for name, usage in user._attrcombined.items():
+                    localusage = node._attrnames.get(name)
+
+                    if usage and localusage:
+                        if not merged.has_key(name):
+                            merged[name] = ObjectSet()
+
+                        for attrnames, value in usage.items():
+                            if attrnames and localusage.issubset(attrnames):
+                                merged[name][attrnames] = value
+
+            node._attrmerged = merged
             node._attrspecifictypes = self._deduce_types(node._attrmerged, objtable)
 
             self._finalise_contributors(node, objtable)