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# family

This folder contains an implementation of the classical family tree Prolog
example. This solution defines a root category, `relations`, with predicates
for common family relations like `sister/2` and `father/2`. This root category
can then be imported into objects defining the actual families using basic
`female/1`, `male/1`, and `parent/2` facts. The relation predicates always
calls the basic facts in _self_. Any number of family objects can be loaded
at the same time.

Print Logtalk, Prolog backend, and kernel versions (if running as a notebook):

```logtalk
%versions
```

Load the example:

```logtalk
logtalk_load(family(loader)).
```

Some example queries using the Addams family relations:

```logtalk
%%table
addams::sister(Sister, Sibling).
```

<!--
Sister = wednesday, Sibling = pubert ;
Sister = wednesday, Sibling = pugsley ;
Sister = wednesday, Sibling = pubert ;
Sister = wednesday, Sibling = pugsley ;
false.
-->

Some example queries using the Simpsons family relations:

```logtalk
%%table
simpsons::mother(Mother, Child).
```

<!--
Mother = marge, Child = bart ;
Mother = marge, Child = lisa ;
Mother = marge, Child = maggie ;
false.
-->
