grscheller.untyped

 1# Copyright 2024 Geoffrey R. Scheller
 2#
 3# Licensed under the Apache License, Version 2.0 (the "License");
 4# you may not use this file except in compliance with the License.
 5# You may obtain a copy of the License at
 6#
 7#     http://www.apache.org/licenses/LICENSE-2.0
 8#
 9# Unless required by applicable law or agreed to in writing, software
10# distributed under the License is distributed on an "AS IS" BASIS,
11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12# See the License for the specific language governing permissions and
13# limitations under the License.
14
15"""
16## Untyped modules
17
18Useful modules I found difficult to implement in a strictly typed manner. Not
19intended to be used with strictly typed code.
20
21### module `grscheller.untyped.nothing`
22
23#### class `Nothing()`
24
25Class representing a non-existent value.
26
27* Nothing() is a singleton
28* Nothing() instances should be compared with the `is` operator, not `==`
29* my[py] becomes problematic when this module is used in a strict typing context
30  * implementing this module with strict typing is vastly more complicated
31  * in client code my[py] keeps warning me about what I am doing
32  * lots of type annotations needed, feels like early Java
33
34#### instance variable: `nothing`
35
36* nothing: Nothing = Nothing() is a singleton
37
38---
39
40"""
41__version__ = "0.1.1"
42__author__ = "Geoffrey R. Scheller"
43__copyright__ = "Copyright (c) 2024 Geoffrey R. Scheller"
44__license__ = "Apache License 2.0"