Merge branch 'master' of github.com:rcoh/SmootLight into behavior-factory

1 files changed, 39 insertions, 0 deletions

diff --git a/util/BehaviorQuerySystem.py b/util/BehaviorQuerySystem.py
new file mode 100644
index 0000000..643b95c
--- /dev/null
+++ b/util/BehaviorQuerySystem.py
@@ -0,0 +1,39 @@
+import types 
+"""The behavior query system is a module that allows querying behaviors based on lambda-function
+predicates."""
+def initBQS():
+    global behaviorList, initialized
+    behaviorList = [] 
+    initialized = True
+
+def addBehavior(behavior):
+    behaviorList.append(behavior)
+
+def query(predicateList):
+    """BehaviorQuerySystem.query takes a list of predicates (functions with signature:
+        (behavior,output)), and
+    optionally a behavior to be compared to."""
+    #want to do queries wrt: behavior itself, the behavior packet, the querying behavior
+    if isinstance(predicateList, types.FunctionType):
+        predicateList = [predicateList]
+    elif not isinstance(predicateList, list):
+        raise Exception('Predicate list must be a function or list of functions')
+    global behaviorList, initialized
+    ret = [] 
+    if not initialized:
+        initBQS()
+    
+    for behavior in behaviorList: #Consider every behavior
+        lastOutput = behavior.getLastOutput()
+        for output in lastOutput: #Look at every element it has output
+            validOutput = True
+            for pred in predicateList: #Evaluate every predicate.  A predicate is a lambda function that
+            #takes a dict and returns a bool.
+                if not pred(output):
+                    validOutput = False
+                    break
+            if validOutput:
+                ret.append(output)
+    return ret 
+
+