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This file is part of Logtalk <https://logtalk.org/>  
Copyright 1998-2021 Paulo Moura <pmoura@logtalk.org>  
SPDX-License-Identifier: Apache-2.0

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
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To load this example and for sample queries, please see the `SCRIPT.txt` file.

This example is inspired by a StackOverflow question for which a sketch of a
Logtalk-based solution was provided:

	http://stackoverflow.com/questions/26119110/knowledge-representation-in-prolog-how-to-store-data

It illustrates a possible solution for representing structured data using
objects and also hot patching of running code. It also shows when a mixed
representation using both data objects and Prolog facts can be managed.

The main files defined in this example are:

- `specs.lgt`  
	defines the recipe protocol, `recipep`, declaring recipe description
	predicates and a prototype object, `proto_recipe`, defining handy
	predicates for summarizing recipe information
- `recipes.lgt`  
	defines some recipes represented as objects
- `parametric.lgt`  
	defines some recipes represented as facts for a `recipe/3` predicate
	plus a `recipe/3` parametric object and a `recipe/1` predicate for
	enumerating recipes while abstracting their representation

- `patch_1.lgt` and `patch_2.lgt`  
	categories used to illustrate hot patching of the example objects
