def compositeToBasicRules(self, pred, body, varOrder = None):
variables = set()
rules = []
rule = Rule()
passOperator = ''
for literal in body:
newLiteral = None
if isinstance(literal, string_types):
for literalString in literal.split('^'):
if re.match('[!#]?[a-z]+[_0-9\([a-zA-Z,]+\)]?' , literalString):
newLiteral = Literal.fromString(literalString)
rule.body.append(newLiteral)
variables = variables.union(newLiteral.vars())
elif re.match('[!#]', literalString):
passOperator = literalString
else:
freshPred = freshPredicate()
(newLiteralVars, newLiteralRules) = Rule.compositeToBasicRules(freshPred, literal)
rules += newLiteralRules
newLiteral = Literal.fromString( passOperator + freshPred + '(' + ','.join(newLiteralVars) + ')')
rule.body.append(newLiteral)
variables = variables.union(newLiteral.vars())
passOperator = ''
if varOrder is not None:
rule.head = Atom.fromString(pred + '(' + varOrder + ')')
else:
rule.head = Atom.fromString(pred + '(' + ','.join(map(str, variables)) + ')')
rules.append(rule)
return (variables, rules)
def fromString(self, string):
newLiteral = Literal()
if string[0] == '!':
newLiteral.op = '!'
newLiteral.atom = Atom.fromString(string[1:])
elif string[0] == '#':
newLiteral.op = '#'
newLiteral.atom = Atom.fromString(string[1:])
else:
newLiteral.op = None
newLiteral.atom = Atom.fromString(string)
return newLiteral
def fromCompositeString(self, string):
newRule = Rule()
newRule.head = Atom.fromString(string.split(':-')[0])
body = string.split(':-')[1].replace(' ', '')
expressions = nestedExpr('[', ']').parseString(body).asList()
(notused, rules) = Rule.compositeToBasicRules(newRule.head.pred, expressions[0], varOrder = ','.join(newRule.head.args))
return reversed(rules)
def fromString(self, string):
newRule = Rule()
string = string.replace(' ','')
tmp = string.split(':-')
newRule.head = Atom.fromString(tmp[0])
if len(tmp) > 1:
for literalString in tmp[1].split('^'):
newRule.body.append(Literal.fromString(literalString))
return newRule
