Added back completion support.

This commit is contained in:
Patrick Lühne 2017-06-01 02:37:45 +02:00
parent c47bd3c934
commit 4baed6fbc6
Signed by: patrick
GPG Key ID: 05F3611E97A70ABF
7 changed files with 144 additions and 165 deletions

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@ -4,6 +4,7 @@
#include <experimental/optional>
#include <anthem/AST.h>
#include <anthem/ASTVisitors.h>
namespace anthem
{
@ -36,12 +37,59 @@ class VariableStack
////////////////////////////////////////////////////////////////////////////////////////////////////
std::vector<VariableDeclaration *> collectFreeVariables(Formula &formula);
std::vector<VariableDeclaration *> collectFreeVariables(Formula &formula, VariableStack &variableStack);
bool matches(const Predicate &lhs, const Predicate &rhs);
void collectPredicates(const Formula &formula, std::vector<const Predicate *> &predicates);
////////////////////////////////////////////////////////////////////////////////////////////////////
// Replacing Variables
////////////////////////////////////////////////////////////////////////////////////////////////////
// Replaces all occurrences of a variable in a given term with another term
struct ReplaceVariableInTermVisitor : public RecursiveTermVisitor<ReplaceVariableInTermVisitor>
{
static void accept(Variable &variable, Term &, const VariableDeclaration *original, VariableDeclaration *replacement)
{
if (variable.declaration == original)
variable.declaration = replacement;
}
// Ignore all other types of expressions
template<class T>
static void accept(T &, Term &, const VariableDeclaration *, VariableDeclaration *)
{
}
};
////////////////////////////////////////////////////////////////////////////////////////////////////
// Replaces all occurrences of a variable in a given formula with a term
struct ReplaceVariableInFormulaVisitor : public RecursiveFormulaVisitor<ReplaceVariableInFormulaVisitor>
{
static void accept(Comparison &comparison, Formula &, const VariableDeclaration *original, VariableDeclaration *replacement)
{
comparison.left.accept(ReplaceVariableInTermVisitor(), comparison.left, original, replacement);
comparison.right.accept(ReplaceVariableInTermVisitor(), comparison.right, original, replacement);
}
static void accept(In &in, Formula &, const VariableDeclaration *original, VariableDeclaration *replacement)
{
in.element.accept(ReplaceVariableInTermVisitor(), in.element, original, replacement);
in.set.accept(ReplaceVariableInTermVisitor(), in.set, original, replacement);
}
static void accept(Predicate &predicate, Formula &, const VariableDeclaration *original, VariableDeclaration *replacement)
{
for (auto &argument : predicate.arguments)
argument.accept(ReplaceVariableInTermVisitor(), argument, original, replacement);
}
// Ignore all other types of expressions
template<class T>
static void accept(T &, Formula &, const VariableDeclaration *, VariableDeclaration *)
{
}
};
////////////////////////////////////////////////////////////////////////////////////////////////////
}

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@ -12,7 +12,7 @@ namespace anthem
//
////////////////////////////////////////////////////////////////////////////////////////////////////
void complete(std::vector<ast::ScopedFormula> &scopedFormulas);
std::vector<ast::Formula> complete(std::vector<ast::ScopedFormula> &&scopedFormulas);
////////////////////////////////////////////////////////////////////////////////////////////////////

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@ -16,56 +16,6 @@ namespace ast
//
////////////////////////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////////////////////
// Replacing Variables
////////////////////////////////////////////////////////////////////////////////////////////////////
// Replaces all occurrences of a variable in a given term with another term
struct ReplaceVariableInTermVisitor : public RecursiveTermVisitor<ReplaceVariableInTermVisitor>
{
static void accept(Variable &variable, Term &, const VariableDeclaration *original, VariableDeclaration *replacement)
{
if (variable.declaration == original)
variable.declaration = replacement;
}
// Ignore all other types of expressions
template<class T>
static void accept(T &, Term &, const VariableDeclaration *, VariableDeclaration *)
{
}
};
////////////////////////////////////////////////////////////////////////////////////////////////////
// Replaces all occurrences of a variable in a given formula with a term
struct ReplaceVariableInFormulaVisitor : public RecursiveFormulaVisitor<ReplaceVariableInFormulaVisitor>
{
static void accept(Comparison &comparison, Formula &, const VariableDeclaration *original, VariableDeclaration *replacement)
{
comparison.left.accept(ReplaceVariableInTermVisitor(), comparison.left, original, replacement);
comparison.right.accept(ReplaceVariableInTermVisitor(), comparison.right, original, replacement);
}
static void accept(In &in, Formula &, const VariableDeclaration *original, VariableDeclaration *replacement)
{
in.element.accept(ReplaceVariableInTermVisitor(), in.element, original, replacement);
in.set.accept(ReplaceVariableInTermVisitor(), in.set, original, replacement);
}
static void accept(Predicate &predicate, Formula &, const VariableDeclaration *original, VariableDeclaration *replacement)
{
for (auto &argument : predicate.arguments)
argument.accept(ReplaceVariableInTermVisitor(), argument, original, replacement);
}
// Ignore all other types of expressions
template<class T>
static void accept(T &, Formula &, const VariableDeclaration *, VariableDeclaration *)
{
}
};
////////////////////////////////////////////////////////////////////////////////////////////////////
// Preparing Copying
////////////////////////////////////////////////////////////////////////////////////////////////////

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@ -192,25 +192,6 @@ struct CollectFreeVariablesVisitor
////////////////////////////////////////////////////////////////////////////////////////////////////
std::vector<VariableDeclaration *> collectFreeVariables(Formula &formula)
{
VariableStack variableStack;
return collectFreeVariables(formula, variableStack);
}
////////////////////////////////////////////////////////////////////////////////////////////////////
std::vector<VariableDeclaration *> collectFreeVariables(Formula &formula, VariableStack &variableStack)
{
std::vector<VariableDeclaration *> freeVariables;
formula.accept(CollectFreeVariablesVisitor(), variableStack, freeVariables);
return freeVariables;
}
////////////////////////////////////////////////////////////////////////////////////////////////////
struct CollectPredicatesVisitor : public RecursiveFormulaVisitor<CollectPredicatesVisitor>
{
static void accept(const Predicate &predicate, const Formula &, std::vector<const Predicate *> &predicates)

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@ -1,8 +1,10 @@
#include <anthem/Completion.h>
#include <anthem/AST.h>
#include <anthem/ASTCopy.h>
#include <anthem/ASTUtils.h>
#include <anthem/ASTVisitors.h>
#include <anthem/Exception.h>
#include <anthem/Utils.h>
namespace anthem
@ -14,33 +16,14 @@ namespace anthem
//
////////////////////////////////////////////////////////////////////////////////////////////////////
// Copies the parameters of a predicate
std::vector<std::unique_ptr<ast::VariableDeclaration>> copyParameters(const ast::Predicate &predicate)
{
std::vector<std::unique_ptr<ast::VariableDeclaration>> parameters;
/*parameters.reserve(predicate.arity());
for (const auto &argument : predicate.arguments)
{
assert(argument.is<ast::Variable>());
// TODO: reimplement
//parameters.emplace_back(ast::deepCopy(parameter.get<ast::VariableDeclaration>()));
}*/
return parameters;
}
////////////////////////////////////////////////////////////////////////////////////////////////////
// Builds the conjunction within the completed formula for a given predicate
ast::Formula buildCompletedFormulaDisjunction(const ast::Predicate &predicate, std::vector<std::unique_ptr<ast::VariableDeclaration>> &parameters, std::vector<ast::ScopedFormula> &scopedFormulas)
ast::Formula buildCompletedFormulaDisjunction(const ast::Predicate &predicate, const ast::VariableDeclarationPointers &parameters, std::vector<ast::ScopedFormula> &scopedFormulas)
{
auto disjunction = ast::Formula::make<ast::Or>();
/*ast::VariableStack variableStack;
variableStack.push(&parameters);
assert(predicate.arguments.size() == parameters.size());
// Build the conjunction of all formulas with the predicate as consequent
// Build the disjunction of all formulas with the predicate as consequent
for (auto &scopedFormula : scopedFormulas)
{
assert(scopedFormula.formula.is<ast::Implies>());
@ -54,18 +37,36 @@ ast::Formula buildCompletedFormulaDisjunction(const ast::Predicate &predicate, s
if (!ast::matches(predicate, otherPredicate))
continue;
auto variables = ast::collectFreeVariables(implies.antecedent, variableStack);
assert(otherPredicate.arguments.size() == parameters.size());
// TODO: avoid deep copies
// TODO: reimplement
if (variables.empty())
disjunction.get<ast::Or>().arguments.emplace_back(ast::deepCopy(implies.antecedent));
// Each formula with the predicate as its consequent currently has its own copy of the predicates parameters
// These need to be linked to the new, unique set of parameters
for (size_t i = 0; i < parameters.size(); i++)
{
assert(otherPredicate.arguments[i].is<ast::Variable>());
const auto &otherVariable = otherPredicate.arguments[i].get<ast::Variable>();
scopedFormula.formula.accept(ast::ReplaceVariableInFormulaVisitor(), scopedFormula.formula, otherVariable.declaration, parameters[i].get());
}
// Remove all the head variables, because they are not free variables after completion
const auto isHeadVariable =
[](const auto &variableDeclaration)
{
return variableDeclaration->type == ast::VariableDeclaration::Type::Head;
};
auto &freeVariables = scopedFormula.freeVariables;
freeVariables.erase(std::remove_if(freeVariables.begin(), freeVariables.end(), isHeadVariable), freeVariables.end());
if (freeVariables.empty())
disjunction.get<ast::Or>().arguments.emplace_back(std::move(implies.antecedent));
else
{
auto exists = ast::Formula::make<ast::Exists>(std::move(variables), ast::deepCopy(implies.antecedent));
auto exists = ast::Formula::make<ast::Exists>(std::move(freeVariables), std::move(implies.antecedent));
disjunction.get<ast::Or>().arguments.emplace_back(std::move(exists));
}
}*/
}
return disjunction;
}
@ -77,7 +78,7 @@ ast::Formula buildCompletedFormulaQuantified(ast::Predicate &&predicate, ast::Fo
{
assert(innerFormula.is<ast::Or>());
/*if (innerFormula.get<ast::Or>().arguments.empty())
if (innerFormula.get<ast::Or>().arguments.empty())
return ast::Formula::make<ast::Not>(std::move(predicate));
if (innerFormula.get<ast::Or>().arguments.size() == 1)
@ -91,72 +92,77 @@ ast::Formula buildCompletedFormulaQuantified(ast::Predicate &&predicate, ast::Fo
return std::move(predicate);
else
return ast::Formula::make<ast::Not>(std::move(predicate));
}*/
}
return ast::Formula::make<ast::Biconditional>(std::move(predicate), std::move(innerFormula));
}
////////////////////////////////////////////////////////////////////////////////////////////////////
void completePredicate(ast::Predicate &&predicate, std::vector<ast::ScopedFormula> &scopedFormulas, std::vector<ast::ScopedFormula> &completedScopedFormulas)
ast::Formula completePredicate(const ast::Predicate &predicate, std::vector<ast::ScopedFormula> &scopedFormulas)
{
/*auto parameters = copyParameters(predicate);
auto completedFormulaDisjunction = buildCompletedFormulaDisjunction(predicate, parameters, scopedFormulas);
auto completedFormulaQuantified = buildCompletedFormulaQuantified(std::move(predicate), std::move(completedFormulaDisjunction));
// Create new set of parameters for the completed definition for the predicate
ast::VariableDeclarationPointers parameters;
parameters.reserve(predicate.arguments.size());
if (parameters.empty())
std::vector<ast::Term> arguments;
arguments.reserve(predicate.arguments.size());
for (size_t i = 0; i < predicate.arguments.size(); i++)
{
completedFormulas.emplace_back(std::move(completedFormulaQuantified));
return;
parameters.emplace_back(std::make_unique<ast::VariableDeclaration>(ast::VariableDeclaration::Type::Head));
arguments.emplace_back(ast::Term::make<ast::Variable>(parameters.back().get()));
}
auto completedFormula = ast::Formula::make<ast::ForAll>(std::move(parameters), std::move(completedFormulaQuantified));
completedFormulas.emplace_back(std::move(completedFormula));*/
ast::Predicate predicateCopy(std::string(predicate.name), std::move(arguments));
auto completedFormulaDisjunction = buildCompletedFormulaDisjunction(predicateCopy, parameters, scopedFormulas);
auto completedFormulaQuantified = buildCompletedFormulaQuantified(std::move(predicateCopy), std::move(completedFormulaDisjunction));
if (parameters.empty())
return completedFormulaQuantified;
return ast::Formula::make<ast::ForAll>(std::move(parameters), std::move(completedFormulaQuantified));
}
////////////////////////////////////////////////////////////////////////////////////////////////////
void completeIntegrityConstraint(ast::Formula &formula, std::vector<ast::ScopedFormula> &)
ast::Formula completeIntegrityConstraint(ast::ScopedFormula &scopedFormula)
{
/*assert(formula.is<ast::Implies>());
auto &implies = formula.get<ast::Implies>();
assert(scopedFormula.formula.is<ast::Implies>());
auto &implies = scopedFormula.formula.get<ast::Implies>();
assert(implies.consequent.is<ast::Boolean>());
assert(implies.consequent.get<ast::Boolean>().value == false);
auto variables = ast::collectFreeVariables(implies.antecedent);
auto argument = ast::Formula::make<ast::Not>(std::move(implies.antecedent));
// TODO: avoid deep copies
// TODO: reimplement
auto argument = ast::Formula::make<ast::Not>(ast::deepCopy(implies.antecedent));
auto &freeVariables = scopedFormula.freeVariables;
if (variables.empty())
{
completedFormulas.emplace_back(std::move(argument));
return;
}
if (freeVariables.empty())
return argument;
auto completedFormula = ast::Formula::make<ast::ForAll>(std::move(variables), std::move(argument));
completedFormulas.emplace_back(std::move(completedFormula));*/
return ast::Formula::make<ast::ForAll>(std::move(freeVariables), std::move(argument));
}
////////////////////////////////////////////////////////////////////////////////////////////////////
void complete(std::vector<ast::ScopedFormula> &scopedFormulas)
std::vector<ast::Formula> complete(std::vector<ast::ScopedFormula> &&scopedFormulas)
{
/*// Check whether formulas are in normal form
// Check whether formulas are in normal form
for (const auto &scopedFormula : scopedFormulas)
{
if (!scopedFormula.formula.is<ast::Implies>())
throw std::runtime_error("cannot perform completion, formula not in normal form");
throw CompletionException("cannot perform completion, formula not in normal form");
auto &implies = scopedFormula.formula.get<ast::Implies>();
if (!implies.consequent.is<ast::Predicate>() && !implies.consequent.is<ast::Boolean>())
throw std::runtime_error("cannot perform completion, only single predicates and Booleans supported as formula consequent currently");
throw CompletionException("cannot perform completion, only single predicates and Booleans supported as formula consequent currently");
}
std::vector<const ast::Predicate *> predicates;
// Get a list of all predicates
for (const auto &scopedFormula : scopedFormulas)
ast::collectPredicates(scopedFormula.formula, predicates);
@ -171,24 +177,11 @@ void complete(std::vector<ast::ScopedFormula> &scopedFormulas)
return lhs->arity() < rhs->arity();
});
std::vector<ast::ScopedFormula> completedScopedFormulas;
std::vector<ast::Formula> completedFormulas;
// Complete predicates
for (const auto *predicate : predicates)
{
// Create the signature of the predicate
ast::Predicate signature(std::string(predicate->name));
signature.arguments.reserve(predicate->arguments.size());
// TODO: reimplement
for (std::size_t i = 0; i < predicate->arguments.size(); i++)
{
auto variableName = std::string(AuxiliaryHeadVariablePrefix) + std::to_string(i + 1);
signature.arguments.emplace_back(ast::Term::make<ast::Variable>(std::move(variableName), ast::VariableDeclaration::Type::Reserved));
}
completePredicate(std::move(signature), scopedFormulas, completedScopedFormulas);
}
completedFormulas.emplace_back(completePredicate(*predicate, scopedFormulas));
// Complete integrity constraints
for (auto &scopedFormula : scopedFormulas)
@ -204,10 +197,10 @@ void complete(std::vector<ast::ScopedFormula> &scopedFormulas)
if (boolean.value == true)
continue;
completeIntegrityConstraint(scopedFormula.formula, completedScopedFormulas);
completedFormulas.emplace_back(completeIntegrityConstraint(scopedFormula));
}
std::swap(scopedFormulas, completedScopedFormulas);*/
return completedFormulas;
}
////////////////////////////////////////////////////////////////////////////////////////////////////

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@ -59,16 +59,26 @@ void translate(const char *fileName, std::istream &stream, Context &context)
for (auto &scopedFormula : scopedFormulas)
simplify(scopedFormula.formula);
if (context.complete)
complete(scopedFormulas);
ast::PrintContext printContext;
if (!context.complete)
{
for (const auto &scopedFormula : scopedFormulas)
{
ast::print(context.logger.outputStream(), scopedFormula.formula, printContext);
context.logger.outputStream() << std::endl;
}
return;
}
auto completedFormulas = complete(std::move(scopedFormulas));
for (const auto &completedFormula : completedFormulas)
{
ast::print(context.logger.outputStream(), completedFormula, printContext);
context.logger.outputStream() << std::endl;
}
}
////////////////////////////////////////////////////////////////////////////////////////////////////

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@ -8,7 +8,7 @@
////////////////////////////////////////////////////////////////////////////////////////////////////
/*TEST_CASE("[completion] Rules are completed", "[completion]")
TEST_CASE("[completion] Rules are completed", "[completion]")
{
std::stringstream input;
std::stringstream output;
@ -75,12 +75,12 @@
CHECK(output.str() ==
"not q\n"
"forall V1 not r(V1)\n"
"forall V1 not s(V1)\n"
"forall V2 not s(V2)\n"
"not t\n"
"forall V1 not u(V1)\n"
"forall V3 not u(V3)\n"
"not q\n"
"not r(5)\n"
"forall N not s(N)\n"
"forall U1 not s(U1)\n"
"not t\n"
"not u(5)\n");
}
@ -126,7 +126,7 @@
CHECK(output.str() ==
"not p\n"
"forall V1 not q(V1)\n"
"forall V1, V2 not t(V1, V2)\n"
"forall V2, V3 not t(V2, V3)\n"
"not v\n");
}
@ -140,12 +140,9 @@
anthem::translate("input", input, context);
CHECK(output.str() ==
"forall V1 (covered(V1) <-> exists I, S (V1 = I and in(I, S)))\n"
"forall V1, V2 (in(V1, V2) <-> (V1 in 1..n and V2 in 1..r and in(V1, V2)))\n"
"forall I not (I in 1..n and not covered(I))\n"
"forall I, S, J not (in(I, S) and in(J, S) and exists X5 (X5 in (I + J) and in(X5, S)))\n");
"forall V1 (covered(V1) <-> exists U1, U2 (V1 = U1 and in(U1, U2)))\n"
"forall V2, V3 (in(V2, V3) <-> (V2 in 1..n and V3 in 1..r and in(V2, V3)))\n"
"forall U3 not (U3 in 1..n and not covered(U3))\n"
"forall U4, U5, U6 not (in(U4, U5) and in(U6, U5) and exists X1 (X1 in (U4 + U6) and in(X1, U5)))\n");
}
// TODO: test collecting free variables
}
*/