Add scan meta op

Makefile

@@ -64,10 +64,8 @@ coverage: test
 	diff-cover coverage.xml --compare-branch=master --fail-under=100
 
 docs:
-	# latesttag=$(git describe --tags `git rev-list --tags --max-count=1`)
-	# echo checking out ${latesttag}
-	# git checkout ${latesttag}
 	pushd docs && \
+	sphinx-apidoc ../symbolic_pymc/ -o source --force && \
 	make html && \
 	ghp-import -n -p -r upstream -b gh-pages build/html && \
 	popd

docs/source/symbolic-pymc-tour.org

@@ -1126,10 +1126,8 @@ like src_python[:eval never]{enable_lvar_defaults}, or by updates to the
 defaults of meta object creation.
 
 Likewise, there are tools available in Symbolic PyMC that make it easier to
-determine why to objects won't unify
-(i.e. src_python[:eval never]{symbolic_pymc.unify.debug_unify}) and exactly
-which components are unequal between two meta objects
-(i.e. src_python[:eval never]{symbolic_pymc.utils.meta_parts_unequal}).
+determine which components are unequal between two meta objects
+(e.g. src_python[:eval never]{symbolic_pymc.utils.meta_parts_unequal}).
 
 Symbolic PyMC's library of relevant mathematical and statistical relations is
 intended to evolve over time.  These relations will reflect useful properties

docs/source/symbolic-pymc-tour.rst

@@ -1071,10 +1071,8 @@ like \ ``enable_lvar_defaults``\ , or by updates to the
 defaults of meta object creation.
 
 Likewise, there are tools available in Symbolic PyMC that make it easier to
-determine why to objects won't unify
-(i.e. \ ``symbolic_pymc.unify.debug_unify``\ ) and exactly
-which components are unequal between two meta objects
-(i.e. \ ``symbolic_pymc.utils.meta_parts_unequal``\ ).
+determine which components are unequal between two meta objects
+(e.g. \ ``symbolic_pymc.utils.meta_parts_unequal``\ ).
 
 Symbolic PyMC's library of relevant mathematical and statistical relations is
 intended to evolve over time.  These relations will reflect useful properties

docs/source/symbolic_pymc.rst

@@ -13,18 +13,18 @@ Subpackages
 Submodules
 ----------
 
-symbolic\_pymc.meta module
---------------------------
+symbolic\_pymc.dispatch module
+------------------------------
 
-.. automodule:: symbolic_pymc.meta
+.. automodule:: symbolic_pymc.dispatch
    :members:
    :undoc-members:
    :show-inheritance:
 
-symbolic\_pymc.unify module
----------------------------
+symbolic\_pymc.meta module
+--------------------------
 
-.. automodule:: symbolic_pymc.unify
+.. automodule:: symbolic_pymc.meta
    :members:
    :undoc-members:
    :show-inheritance:

docs/source/symbolic_pymc.tensorflow.rst

@@ -4,6 +4,22 @@ symbolic\_pymc.tensorflow package
 Submodules
 ----------
 
+symbolic\_pymc.tensorflow.dispatch module
+-----------------------------------------
+
+.. automodule:: symbolic_pymc.tensorflow.dispatch
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+symbolic\_pymc.tensorflow.graph module
+--------------------------------------
+
+.. automodule:: symbolic_pymc.tensorflow.graph
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
 symbolic\_pymc.tensorflow.meta module
 -------------------------------------
 
@@ -20,14 +36,6 @@ symbolic\_pymc.tensorflow.printing module
    :undoc-members:
    :show-inheritance:
 
-symbolic\_pymc.tensorflow.unify module
---------------------------------------
-
-.. automodule:: symbolic_pymc.tensorflow.unify
-   :members:
-   :undoc-members:
-   :show-inheritance:
-
 
 Module contents
 ---------------

docs/source/symbolic_pymc.theano.rst

@@ -4,6 +4,14 @@ symbolic\_pymc.theano package
 Submodules
 ----------
 
+symbolic\_pymc.theano.dispatch module
+-------------------------------------
+
+.. automodule:: symbolic_pymc.theano.dispatch
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
 symbolic\_pymc.theano.meta module
 ---------------------------------
 
@@ -52,14 +60,6 @@ symbolic\_pymc.theano.random\_variables module
    :undoc-members:
    :show-inheritance:
 
-symbolic\_pymc.theano.unify module
-----------------------------------
-
-.. automodule:: symbolic_pymc.theano.unify
-   :members:
-   :undoc-members:
-   :show-inheritance:
-
 symbolic\_pymc.theano.utils module
 ----------------------------------
 

requirements.txt

@@ -1,3 +1,5 @@
+setuptools>=45.2.0
+six>=1.14.0
 -e ./
 sympy>=1.3
 coveralls

setup.py

@@ -32,6 +32,7 @@ def get_long_description():
     author_email=AUTHOR_EMAIL,
     url=URL,
     install_requires=[
+        "numpy>=1.18.1",
         "scipy>=1.4.0",
         "Theano>=1.0.4",
         "tf-estimator-nightly==2.1.0.dev2020012309",

symbolic_pymc/__init__.py

@@ -1,5 +1,5 @@
 # We need this so that `multipledispatch` initialization occurs
-from .unify import *
+from .dispatch import *
 
 from ._version import get_versions
 

symbolic_pymc/unify.py → symbolic_pymc/dispatch.py

@@ -1,4 +1,3 @@
-from functools import wraps
 from collections.abc import Mapping
 
 from cons.core import _car, _cdr, ConsError
@@ -13,36 +12,6 @@
 from .meta import MetaSymbol, MetaVariable
 
 
-class UnificationFailure(Exception):
-    pass
-
-
-def debug_unify(enable=True):  # pragma: no cover
-    """Wrap unify functions so that they raise a `UnificationFailure` exception when unification fails."""
-    if enable:
-
-        def set_debug(f):
-            @wraps(f)
-            def wrapper(*args, **kwargs):
-                s = f(*args, **kwargs)
-                if s is False:
-                    import pdb
-
-                    pdb.set_trace()
-                    raise UnificationFailure()
-                return s
-
-            return wrapper
-
-        _unify.funcs = {
-            sig: set_debug(getattr(f, "__wrapped__", f)) for sig, f in _unify.funcs.items()
-        }
-        _unify._cache.clear()
-    else:
-        _unify.funcs = {sig: getattr(f, "__wrapped__", f) for sig, f in _unify.funcs.items()}
-        _unify._cache.clear()
-
-
 def unify_MetaSymbol(u, v, s):
     if type(u) != type(v):
         return False
@@ -157,6 +126,3 @@ def cdr_MetaVariable(x):
 
 # arguments.add((MetaSymbol,), cdr_MetaSymbol)
 arguments.add((MetaVariable,), cdr_MetaVariable)
-
-
-__all__ = ["debug_unify"]

symbolic_pymc/meta.py

@@ -335,7 +335,12 @@ def __ne__(self, other):
         return not self.__eq__(other)
 
     def __hash__(self):
-        return hash((self.base, self.rands))
+        try:
+            rands = self.rands
+        except NotImplementedError:  # pragma: no cover
+            return NotImplemented
+
+        return hash((self.base, rands))
 
     def __str__(self):
         return self.__repr__(show_obj=False, _repr=str)

symbolic_pymc/relations/theano/__init__.py

@@ -1,22 +1,56 @@
+import numpy as np
+import theano.tensor as tt
+
 from unification import var
+from unification.utils import transitive_get as walk
 
 from kanren import eq
 from kanren.core import lall, Zzz
 from kanren.facts import fact
 from kanren.graph import applyo, walko
 from kanren.assoccomm import commutative, associative
+from kanren.constraints import neq
 
 from etuples import etuple
 
-from ...theano.meta import mt
-
+from ...utils import HashableNDArray
+from ...theano.meta import TheanoMetaConstant, mt
 
+# Establish some Theano `Op`s as commutative and/or associative
 fact(commutative, mt.add)
 fact(commutative, mt.mul)
 fact(associative, mt.add)
 fact(associative, mt.mul)
 
 
+def constant_neq(lvar, val):
+    """Assert that a constant graph variable is not equal to a specific value.
+
+    Scalar values are broadcast across arrays.
+
+    XXX: This goal is non-relational.
+    TODO: Rewrite this as an actual constraint.
+    """
+
+    if isinstance(val, np.ndarray):
+        val = val.view(HashableNDArray)
+
+    def constant_neq_goal(S):
+        lvar_rf = walk(lvar, S)
+        if isinstance(lvar_rf, (tt.Constant, TheanoMetaConstant)):
+            # Although `neq` is an actual constraint, the preceding type check
+            # and alternative success--when not a constant type--make the
+            # entire goal non-relational/not a true constraint, since the
+            # aforementioned check will only occur once per goal-stream/state
+            # and never again.
+            yield from neq(lvar_rf.data, val)(S)
+        else:
+            # When the value isn't a Theano constant, consider it satisfied
+            yield S
+
+    return constant_neq_goal
+
+
 def non_obs_walko(relation, a, b):
     """Construct a goal that applies a relation to all nodes above an observed random variable.
 

symbolic_pymc/relations/theano/distributions.py

@@ -1,19 +1,14 @@
 """Relations pertaining to probability distributions."""
-import numpy as np
-import theano.tensor as tt
-
 from unification import var
-from unification.utils import transitive_get as walk
 
 from etuples import etuple
 
 from kanren import conde, eq
 from kanren.facts import fact, Relation
-from kanren.constraints import neq
 
+from . import constant_neq
 from .. import concat
-from ...utils import HashableNDArray
-from ...theano.meta import TheanoMetaConstant, mt
+from ...theano.meta import mt
 
 
 derived_dist = Relation("derived_dist")
@@ -57,28 +52,6 @@
 #      None)
 
 
-def constant_neq(lvar, val):
-    """Assert that a constant graph variable is not equal to a specific value.
-
-    Scalar values are broadcast across arrays.
-
-    XXX: This goal is non-relational
-    """
-
-    if isinstance(val, np.ndarray):
-        val = val.view(HashableNDArray)
-
-    def constant_neq_goal(S):
-        lvar_rf = walk(lvar, S)
-        if isinstance(lvar_rf, (tt.Constant, TheanoMetaConstant)):
-            # TODO: Can we get away with `neq(lvar_rf, val)` alone?
-            yield from neq(lvar_rf.data, val)(S)
-        else:
-            yield S
-
-    return constant_neq_goal
-
-
 def scale_loc_transform(in_expr, out_expr):
     """Create relations for lifting and sinking scale and location parameters of distributions.
 

symbolic_pymc/tensorflow/__init__.py

@@ -1,2 +1,2 @@
 # Needed to register generic functions
-from .unify import *
+from .dispatch import *

symbolic_pymc/tensorflow/unify.py → symbolic_pymc/tensorflow/dispatch.py

@@ -12,7 +12,7 @@
 
 from .meta import TFlowMetaSymbol
 from ..meta import metatize
-from ..unify import unify_MetaSymbol
+from ..dispatch import unify_MetaSymbol
 
 tf_class_abstractions = tuple(c.base for c in TFlowMetaSymbol.base_subclasses())
 

symbolic_pymc/theano/__init__.py

@@ -1,2 +1,2 @@
 # Needed to register generic functions
-from .unify import *
+from .dispatch import *

symbolic_pymc/theano/unify.py → symbolic_pymc/theano/dispatch.py

@@ -13,7 +13,7 @@
 
 from .meta import TheanoMetaSymbol
 from ..meta import metatize
-from ..unify import unify_MetaSymbol
+from ..dispatch import unify_MetaSymbol
 
 
 tt_class_abstractions = tuple(c.base for c in TheanoMetaSymbol.base_subclasses())