simple.prolog source

sibling(X,Y) :- parent(Z,X), parent(Z,Y).
parent(X,Y) :- father(X,Y).
parent(X,Y) :- mother(X,Y).
mother(trude, sally).
father(tom, sally).
father(tom, erica).
father(mike, tom).
female(trude).
male(tom).
male(mike).

/*<html>
<head>
     <title>Simple PSP Demo</title>
</head>
<body>

<a href="template.prolog?t=psp#psp">Back</a><br>
<a href="simple.html">View Source</a><br><br>

<?, father(Dad, sally) ,?>

Sally's father is <?= Dad ?> <br><br>

The following people are siblings: <br>

<?, forall(sibling(X, Y), ?> "<?= X ?>" is a sibling of "<?= Y ?>". <br> <?) ,?>

</body>
</html>*/