Merge pull request #56 from ngeiswei/improv-cogscm-syntax

Improve cogscm syntax

rocca/agents/utils.py

@@ -8,7 +8,7 @@
 import random
 import math
 from typing import Any
-
+from functools import cmp_to_key
 from orderedmultidict import omdict
 
 # SciPy
@@ -395,6 +395,18 @@ def has_variables_leq(cogscm: Atom, vc: int) -> bool:
     return vardecl_size(get_vardecl(cogscm)) <= vc
 
 
+def is_ordered(atom: Atom) -> bool:
+    """Return true iff the atom inherits from the OrderedLink type."""
+
+    return is_a(atom.type, types.OrderedLink)
+
+
+def is_unordered(atom: Atom) -> bool:
+    """Return true iff the atom inherits from the UnorderedLink type."""
+
+    return is_a(atom.type, types.UnorderedLink)
+
+
 def is_virtual(clause: Atom) -> bool:
     """Return true iff the clause is virtual.
 
@@ -1003,10 +1015,42 @@ def get_uniq_atoms(atom: Atom) -> set[Atom]:
     return result
 
 
+def syntax_lt(a1: Atom, a2: Atom) -> bool:
+    """Custom less-than function for unordered links.
+
+    It is used by to_human_readable_str to place the do(Action) to the
+    right, so that for instance
+
+    do(Eat) ∧ AgentPosition(RightSquare) ↝ Reward(1)
+
+    becomes
+
+    AgentPosition(RightSquare) ∧ do(Eat) ↝ Reward(1)
+
+    which makes it easier to read and search.
+
+    """
+
+    return (not is_execution(a1) and is_execution(a2)) or a1 < a2
+
+
+def syntax_cmp(a1: Atom, a2: Atom) -> int:
+    """Compare function based on syntax_lt for to_human_readable_str."""
+
+    if a1 == a2:
+        return 0
+    elif syntax_lt(a1, a2):
+        return -1
+    else:
+        return 1
+
+
 def syntax_precede(a1: Atom, a2: Atom) -> bool:
+
     """Return true iff a1 syntactically precedes a2.
 
-    This function is used by to_human_readable_str
+    This function is used by to_human_readable_str to minimize the
+    number of parenthesis.
 
     Precedence order is as follows
 
@@ -1182,6 +1226,8 @@ def to_human_readable_str(atom: Atom, parenthesis: bool = False) -> str:
         is_infix = False
     else:
         out = atom.out
+        if is_unordered(atom):
+            out = sorted(out, key=cmp_to_key(syntax_cmp))
         op_str = type_to_human_readable_str(atom.type)
 
     # Recursively convert outgoings to human readable strings, adding

tests/agents/test_utils.py

@@ -198,12 +198,9 @@ def test_to_human_readable_str():
     )
 
     cogscm_hrs_1 = to_human_readable_str(cogscm_1)
+    expected_1 = "outside(self, house) ∧ do(go_to_key) ↝ hold(self, key)"
 
-    # Two expected results due to AndLink commutativity
-    expected_1a = "outside(self, house) ∧ do(go_to_key) ↝ hold(self, key)"
-    expected_1b = "do(go_to_key) ∧ outside(self, house) ↝ hold(self, key)"
-
-    assert cogscm_hrs_1 == expected_1a or cogscm_hrs_1 == expected_1b
+    assert cogscm_hrs_1 == expected_1
 
     # 2. AgentPosition(RightSquare) ∧ do(Eat) ↝ Reward(1)
     # Check that whitespace is removed in names
@@ -220,12 +217,9 @@ def test_to_human_readable_str():
     )
 
     cogscm_hrs_2 = to_human_readable_str(cogscm_2)
+    expected_2 = "AgentPosition(RightSquare) ∧ do(Eat) ↝ Reward(1)"
 
-    # Two expected results due to AndLink commutativity
-    expected_2a = "AgentPosition(RightSquare) ∧ do(Eat) ↝ Reward(1)"
-    expected_2b = "do(Eat) ∧ AgentPosition(RightSquare) ↝ Reward(1)"
-
-    assert cogscm_hrs_2 == expected_2a or cogscm_hrs_2 == expected_2b
+    assert cogscm_hrs_2 == expected_2
 
     # 3. -0.01 > $angle ∧ PoleAngle($angle) ∧ do(GoLeft) ↝ Reward(1)
     # Test with variable and GreaterThanLink
@@ -242,19 +236,9 @@ def test_to_human_readable_str():
 
     cogscm_hrs_3 = to_human_readable_str(cogscm_3)
 
-    # Six expected results due to AndLink commutativity
+    # Two expected results due to AndLink commutativity (in spite of
+    # actions being moved to the right)
     expected_3a = "-0.01 > $angle ∧ PoleAngle($angle) ∧ do(GoLeft) ↝ Reward(1)"
-    expected_3b = "-0.01 > $angle ∧ do(GoLeft) ∧ PoleAngle($angle) ↝ Reward(1)"
-    expected_3c = "do(GoLeft) ∧ -0.01 > $angle ∧ PoleAngle($angle) ↝ Reward(1)"
-    expected_3d = "PoleAngle($angle) ∧ -0.01 > $angle ∧ do(GoLeft) ↝ Reward(1)"
-    expected_3e = "PoleAngle($angle) ∧ -0.01 > $angle ∧ do(GoLeft) ↝ Reward(1)"
-    expected_3f = "PoleAngle($angle) ∧ do(GoLeft) ∧ -0.01 > $angle ↝ Reward(1)"
-
-    assert (
-        cogscm_hrs_3 == expected_3a
-        or cogscm_hrs_3 == expected_3b
-        or cogscm_hrs_3 == expected_3c
-        or cogscm_hrs_3 == expected_3d
-        or cogscm_hrs_3 == expected_3e
-        or cogscm_hrs_3 == expected_3f
-    )
+    expected_3b = "PoleAngle($angle) ∧ -0.01 > $angle ∧ do(GoLeft) ↝ Reward(1)"
+
+    assert cogscm_hrs_3 == expected_3a or cogscm_hrs_3 == expected_3b