Make options a nested class of KnuthBendix

Author: james-d-mitchell

docs/source/main-algorithms/knuth-bendix/class.rst

@@ -47,3 +47,4 @@ Full API
 .. autoclass:: KnuthBendixRewriteTrie
    :class-doc-from: init
    :members:
+   :exclude-members: options

docs/source/main-algorithms/knuth-bendix/index.rst

@@ -16,4 +16,4 @@ in ``libsemigroups_pybind11``.
 
    class 
    helpers
-   overlap
+   nested 

docs/source/main-algorithms/knuth-bendix/nested.rst

@@ -0,0 +1,18 @@
+.. Copyright (c) 2024 J. D. Mitchell
+
+   Distributed under the terms of the GPL license version 3.
+
+   The full license is in the file LICENSE, distributed with this software.
+
+.. currentmodule:: libsemigroups_pybind11
+
+The options nested class
+========================
+
+This page contains documentation for the nested class
+:any:`KnuthBendixRewriteTrie.options` which holds various values that can be used
+to control the behaviour of Knuth-Bendix.
+
+.. autoclass:: _libsemigroups_pybind11::KnuthBendixRewriteTrie.options
+   :members:
+   :exclude-members: name

docs/source/main-algorithms/knuth-bendix/overlap.rst

@@ -47,7 +47,6 @@
         lexicographical_compare,
         recursive_path_compare,
         shortlex_compare,
-        overlap,
         to_presentation,
         to_inverse_presentation,
         LibsemigroupsError,

libsemigroups_pybind11/__init__.py

@@ -84,18 +84,21 @@ def KnuthBendix(*args, rewriter="RewriteTrie"):  # pylint: disable=invalid-name
     return result
 
 
-# The next function (non_trivial_classes) is documented here not in the cpp
-# file because we add the additional kwarg Word.
+KnuthBendix.options = _KnuthBendixRewriteTrie.options
 
 
+# The next function (non_trivial_classes) is documented here not in the cpp
+# file because we add the additional kwarg Word.
 @_template_params_as_kwargs(
     Word={
         str: _knuth_bendix_str_non_trivial_classes,
         List[int]: _knuth_bendix_word_non_trivial_classes,
     }
 )
 def non_trivial_classes(
-    kb1: KnuthBendix, kb2: KnuthBendix, **kwargs
+    kb1: KnuthBendix,
+    kb2: KnuthBendix,
+    **kwargs,  # pylint: disable=unused-argument
 ) -> List[List[str | List[int]]]:
     r"""
     Find the non-trivial classes of the quotient of one KnuthBendix instance in
@@ -173,7 +176,7 @@ def non_trivial_classes(
         List[int]: _knuth_bendix_word_normal_forms,
     }
 )
-def normal_forms(kb: KnuthBendix, **kwargs) -> Iterator[str | List[int]]:
+def normal_forms(kb: KnuthBendix, **kwargs) -> Iterator[str | List[int]]:  # pylint: disable=unused-argument
     r"""
     Returns an iterator yielding normal forms.
 

libsemigroups_pybind11/knuth_bendix.py

@@ -247,7 +247,8 @@ This class is used to represent a `string rewriting system
 presented monoid or semigroup.
 
 :any:`KnuthBendixRewriteTrie` inherits from :any:`Runner` and
-:any:`CongruenceInterface`.
+:any:`CongruenceInterface`; and has the nested class
+:any:`KnuthBendixRewriteTrie.options`.
 
  .. doctest::
 
@@ -269,6 +270,33 @@ presented monoid or semigroup.
     True
 )pbdoc");
 
+      py::class_<typename KnuthBendix<Rewriter>::options> options(kb,
+                                                                  "options",
+                                                                  R"pbdoc(
+This class containing various options that can be used to control the
+behaviour of Knuth-Bendix.)pbdoc");
+
+      py::enum_<typename KnuthBendix<Rewriter>::options::overlap>(options,
+                                                                  "overlap",
+                                                                  R"pbdoc(
+Values for specifying how to measure the length of an overlap.
+
+The values in this enum determine how a :any:`KnuthBendixRewriteTrie`
+instance measures the length :math:`d(AB, BC)` of the overlap of
+two words :math:`AB` and :math:`BC`.
+
+.. seealso:: :any:`KnuthBendixRewriteTrie.overlap_policy`
+)pbdoc")
+          .value("ABC",
+                 KnuthBendix<Rewriter>::options::overlap::ABC,
+                 R"pbdoc(:math:`d(AB, BC) = |A| + |B| + |C|`)pbdoc")
+          .value("AB_BC",
+                 KnuthBendix<Rewriter>::options::overlap::AB_BC,
+                 R"pbdoc(:math:`d(AB, BC) = |AB| + |BC|`)pbdoc")
+          .value("MAX_AB_BC",
+                 KnuthBendix<Rewriter>::options::overlap::MAX_AB_BC,
+                 R"pbdoc(:math:`d(AB, BC) = max(|AB|, |BC|)`)pbdoc");
+
       kb.def("__repr__", [](KnuthBendix<Rewriter>& kb) {
         return to_human_readable_repr(kb);
       });
@@ -902,38 +930,6 @@ semigroup or monoid defined by the :py:class:`KnuthBendixRewriteTrie` object
   }  // namespace
 
   void init_knuth_bendix(py::module& m) {
-    // TODO better repr?
-    // TODO(1) this isn't done properly since there's not options object
-    // registered, so referring to "options.overlap" doesn't work
-    py::enum_<KnuthBendix<>::options::overlap>(m,
-                                               "overlap",
-                                               R"pbdoc(
-Values for specifying how to measure the length of an overlap.
-
-The values in this enum determine how a :any:`KnuthBendixRewriteTrie`
-instance measures the length :math:`d(AB, BC)` of the overlap of
-two words :math:`AB` and :math:`BC`.
-
-.. seealso:: :any:`KnuthBendixRewriteTrie.overlap_policy`
-)pbdoc")
-        .value("ABC",
-               KnuthBendix<>::options::overlap::ABC,
-               R"pbdoc(
-
-:math:`d(AB, BC) = |A| + |B| + |C|`
-)pbdoc")
-        .value("AB_BC",
-               KnuthBendix<>::options::overlap::AB_BC,
-               R"pbdoc(
-
-:math:`d(AB, BC) = |AB| + |BC|`
-)pbdoc")
-        .value("MAX_AB_BC",
-               KnuthBendix<>::options::overlap::MAX_AB_BC,
-               R"pbdoc(
-
-:math:`d(AB, BC) = max(|AB|, |BC|)`
-)pbdoc");
     bind_knuth_bendix<detail::RewriteFromLeft>(m, "KnuthBendixRewriteFromLeft");
     bind_knuth_bendix<detail::RewriteTrie>(m, "KnuthBendixRewriteTrie");
   }

src/knuth-bendix.cpp

@@ -23,7 +23,6 @@
     presentation,
     LibsemigroupsError,
     POSITIVE_INFINITY,
-    overlap,
     is_obviously_infinite,
 )
 
@@ -119,8 +118,7 @@ def test_attributes():
     assert kb.check_confluence_interval() == 4096
     assert kb.max_overlap() == POSITIVE_INFINITY
     assert kb.max_rules() == POSITIVE_INFINITY
-    assert isinstance(kb.overlap_policy(), overlap)
-    assert kb.overlap_policy() == overlap.ABC
+    assert kb.overlap_policy() == kb.options.overlap.ABC
     assert kb.presentation().alphabet() == "abBe"
     assert kb.number_of_active_rules() == 12
     assert kb.number_of_inactive_rules() == 0