def simplify_facts(db, facts, vars_to_keep):
assert isinstance(facts, list), facts
assert all(isinstance(f, Expression) for f in facts), facts
assert isinstance(vars_to_keep, set), vars_to_keep
assert all(isinstance(v, Expression) for v in vars_to_keep), vars_to_keep
assert all(v.is_var() for v in vars_to_keep), vars_to_keep
facts = set(simplify_expr(f) for f in facts)
facts = simplify_defs(facts, vars_to_keep)
strings = db.simplify([f.polish for f in facts])
facts = set(parse_string_to_expr(s) for s in strings)
facts = map(unguard_vars, facts)
return facts
def compile_solver(expr, theory):
'''
Produces a set of programs that finds values of term satisfying a theory.
Inputs:
expr - string, an expression with free variables
theory - string representing a theory (in .theory format)
Outputs:
a program to be consumed by the virtual machine
Example:
expr = 's'
theory = """
# 6 constraints = 4 facts + 2 rules
LESS APP V s s NLESS x BOT NLESS x I
LESS APP s BOT BOT -------------- ----------------
EQUAL APP s I I LESS I APP s x LESS TOP APP s x
LESS TOP APP s TOP
"""
'''
assert isinstance(expr, basestring), expr
assert isinstance(theory, basestring), theory
expr = desugar_expr(parse_string_to_expr(expr))
assert expr.vars, expr
theory = parse_theory_string(theory)
facts = map(desugar_expr, theory['facts'])
rules = map(desugar_sequent, theory['rules'])
sequents = []
can_infer_necessary = not rules and all(f.vars <= expr.vars for f in facts)
can_infer_possible = expr.is_var() # TODO generalize to injective exprs
if can_infer_necessary:
sequents.append(Sequent(facts, [NONEGATE(RETURN(expr))]))
if can_infer_possible:
fail = NONEGATE(NRETURN(expr))
sequents += [Sequent([], [f, fail]) for f in facts]
sequents += [
Sequent(r.antecedents, set_with(r.succedents, fail))
for r in rules
]
assert sequents, 'Cannot infer anything'
programs = []
write_full_programs(programs, sequents, can_parallelize=False)
program = '\n'.join(programs)
assert not re.search('FOR_BLOCK', program), 'cannot parallelize'
return program
def parse_expr(string):
return desugar_expr(parse_string_to_expr(string))
def pythonize_expr(proto_expr):
return parse_string_to_expr(proto_expr.polish)
def desugar(string):
expr = parse_string_to_expr(string)
expr = desugar_expr(expr)
expr = guard_vars(expr)
return str(expr)
def test_hole_filler_increases_complexity(example):
term = parse_string_to_expr(example[0])
fillings = list(fill_holes(term))
for f in fillings:
assert evaluate_complexity(term) < evaluate_complexity(f)
def test_hole_filler(example):
term = parse_string_to_expr(example[0])
expected = map(parse_string_to_expr, example[1])
actual = list(fill_holes(term))
assert actual == expected
def test_complexity_evaluator(example):
term = parse_string_to_expr(example)
assert 0 < evaluate_complexity(term)
def _db_simplify_expr(db, expr):
string = db.simplify([expr.polish])[0]
expr = parse_string_to_expr(string)
expr = unguard_vars(expr)
return expr