Refactor py3

.github/workflows/package_lint-test.yml

@@ -12,11 +12,11 @@ on:
 jobs:
   build:
 
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04  # py36 is EOL on ubuntu-latest
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.8", "3.9", "3.10", "3.11", "pypy3.9"]
+        python-version: ["3.6", "3.7", "3.8", "3.9", "3.10", "3.11", "pypy3.9"]
 
     steps:
     - uses: actions/checkout@v3

README.rst

@@ -3,8 +3,6 @@ Priority Queue Dictionary (pqdict)
 
 A priority queue dictionary maps hashable objects (keys) to priority-determining values. It provides a hybrid dictionary/priority queue API. 
 
-Works with Python 2.7+, 3.4+, and PyPy.
-
 .. image:: https://github.com/nvictus/priority-queue-dictionary/actions/workflows/package_lint-test.yml/badge.svg
     :target: https://github.com/nvictus/priority-queue-dictionary/actions/workflows/package_lint-test.yml
     :alt: CI

docs/conf.py

@@ -86,7 +86,7 @@ def _get_version():
 #
 # This is also used if you do content translation via gettext catalogs.
 # Usually you set "language" from the command line for these cases.
-language = None
+language = "en"
 
 # There are two options for replacing |today|: either, you set today to some
 # non-false value, then it is used:

docs/pqdict.rst

@@ -12,9 +12,11 @@ pqdict class
 .. autoclass:: pqdict
     :no-members:
 
-    .. automethod:: fromkeys
+    .. automethod:: minpq
 
-    .. automethod:: heapify([key])
+    .. automethod:: maxpq
+
+    .. automethod:: fromkeys
 
     |
 
@@ -44,9 +46,14 @@ pqdict class
 
     .. method:: pop([key[, default]])
 
-        If ``key`` is in the pqdict, remove it and return its priority value,
-        else return ``default``. If ``default`` is not provided and ``key`` is
-        not in the pqdict, raise a ``KeyError``.
+        Hybrid pop method.
+
+        With ``key``, perform a dictionary pop:
+
+        * If ``key`` is in the pqdict, remove the item and return its
+          **value**.
+        * If ``key`` is not in the pqdict, return ``default`` if provided,
+          otherwise raise a ``KeyError``.
 
     .. automethod:: clear 
 
@@ -59,7 +66,9 @@ pqdict class
     Iterators and Views
 
     .. warning:: 
-        For the following sequences, order is arbitrary.
+        For the sequences returned by the following methods, the **iteration order is arbitrary**.
+
+        See further below for sorted iterators :meth:`popkeys`, :meth:`popvalues`, and :meth:`popitems`.
 
     .. method:: iter(pq)
 
@@ -69,53 +78,56 @@ pqdict class
 
     .. automethod:: items
 
-    .. note::
-        In Python 2, the above methods return lists rather than views and ``pqdict`` includes additional iterator methods ``iterkeys()``, ``itervalues()`` and ``iteritems()``.
-
     |
 
     **Priority Queue API**
 
     .. automethod:: top
 
     .. automethod:: topvalue
+
+    .. automethod:: topitem
 
-    .. method:: pop([key[, default]])
+    .. method:: pop(*, [default])
 
-        If ``key`` is not provided, remove the top item and return its key, or
-        raise ``KeyError`` if the pqdict is empty.
+        Hybrid pop method.
 
-    .. automethod:: additem
+        Without ``key``, perform a priority queue pop:
 
-    .. automethod:: updateitem
-
-    .. automethod:: topitem
+        * Remove the top item and return its **key**.
+        * If the pqdict is empty, return ``default`` if provided, otherwise
+          raise a ``KeyError``.
 
+    .. automethod:: popvalue
+
     .. automethod:: popitem
 
+    .. automethod:: additem
+
+    .. automethod:: updateitem
+
     .. automethod:: pushpopitem(key, value)
 
     .. automethod:: replace_key
 
     .. automethod:: swap_priority
 
-    Heapsort Iterators
+    .. automethod:: heapify([key])
+
+    Sorted Iterators
 
     .. note::
         Iteration is in descending order of priority.
 
-    .. danger::
-        Heapsort iterators are destructive: they are generators that pop items out of the heap, which amounts to performing a heapsort.
+    .. warning::
+        Sorted iterators are destructive: they are generators that pop items out of the heap, which amounts to performing a heapsort.
 
     .. automethod:: popkeys
 
     .. automethod:: popvalues 
 
     .. automethod:: popitems
 
-    .. warning::
-        The names of the heapsort iterators in v0.5 (iterkeys, itervalues, iteritems) were changed in v0.6 to be more transparent: These names are not provided at all in Python 3, and in Python 2 they are now part of the dictionary API.
-
 
 Functions
 ---------