Math::Logic::Predicate 0.03

Math::Logic::Predicate is a Perl module to manage and query a predicate assertion database.

SYNOPSIS

use Math::Logic::Predicate;

$db = new Math::Logic::Predicate;

# Enter some predicates into the database
$db->add(<<EOA);
human(lister).
human(kochanski).
plays(lister, guitar).
smart(holly).
smart(rimmer).
name(lister, Dave Lister).
name(kochanski, Kristine Kochanski).
name(rimmer, Arnold Rimmer).
EOA

# Retract a predicate
$db->retract( plays(lister, guitar) );
# Or based on a pattern
$db->retract( smart(_) );

# Make a query
$query = $db->parse( human(H) & name(H, X) ? );
$iter = $db->match($query, $iter);

# Get the results
$name = $db->get($iter, X);

# Store it in a rule
$db->add( human_name(H, N) := human(H) & name(H, N). );

# Use it in a query
$iter = $db->match( human_name(lister, N) ? );

# Save it to a file
use Storable;
store($db->rules, red_dwarf);