anthem-rs/src/translate/common/choose_value_in_term.rs

265 lines
10 KiB
Rust

pub(crate) fn choose_value_in_primitive(term: Box<foliage::Term>,
variable_declaration: &std::rc::Rc<foliage::VariableDeclaration>)
-> foliage::Formula
{
let variable = foliage::Term::variable(variable_declaration);
foliage::Formula::equal(Box::new(variable), term)
}
pub(crate) fn choose_value_in_term<C>(term: &clingo::ast::Term,
variable_declaration: &std::rc::Rc<foliage::VariableDeclaration>, context: &C)
-> Result<foliage::Formula, crate::Error>
where
C: crate::translate::common::GetOrCreateFunctionDeclaration
+ crate::translate::common::GetOrCreateVariableDeclaration
+ crate::translate::common::AssignVariableDeclarationDomain
{
match term.term_type()
{
clingo::ast::TermType::Symbol(symbol) => match symbol.symbol_type()
.map_err(|error| crate::Error::new_logic("clingo error").with(error))?
{
clingo::SymbolType::Number => Ok(choose_value_in_primitive(
Box::new(foliage::Term::integer(symbol.number()
.map_err(|error| crate::Error::new_logic("clingo error").with(error))?)),
variable_declaration)),
clingo::SymbolType::Infimum => Ok(choose_value_in_primitive(
Box::new(foliage::Term::infimum()), variable_declaration)),
clingo::SymbolType::Supremum => Ok(choose_value_in_primitive(
Box::new(foliage::Term::supremum()), variable_declaration)),
clingo::SymbolType::String => Ok(choose_value_in_primitive(
Box::new(foliage::Term::string(symbol.string()
.map_err(|error| crate::Error::new_logic("clingo error").with(error))?
.to_string())),
variable_declaration)),
clingo::SymbolType::Function =>
{
let arguments = symbol.arguments()
.map_err(|error| crate::Error::new_logic("clingo error").with(error))?;
// Functions with arguments are represented as clingo::ast::Function by the parser.
// At this point, we only have to handle (0-ary) constants
if !arguments.is_empty()
{
return Err(crate::Error::new_logic("unexpected arguments, expected (0-ary) constant symbol"));
}
let constant_name = symbol.name()
.map_err(|error| crate::Error::new_logic("clingo error").with(error))?;
let constant_declaration = context.get_or_create_function_declaration(constant_name, 0);
let function = foliage::Term::function(&constant_declaration, vec![]);
Ok(choose_value_in_primitive(Box::new(function), variable_declaration))
}
},
clingo::ast::TermType::Variable(variable_name) =>
{
let other_variable_declaration = context.get_or_create_variable_declaration(
variable_name);
context.assign_variable_declaration_domain(&other_variable_declaration,
crate::Domain::Program);
let other_variable = foliage::Term::variable(&other_variable_declaration);
Ok(choose_value_in_primitive(Box::new(other_variable), variable_declaration))
},
clingo::ast::TermType::BinaryOperation(binary_operation) =>
{
let operator = super::translate_binary_operator(binary_operation.binary_operator())?;
match operator
{
foliage::BinaryOperator::Add
| foliage::BinaryOperator::Subtract
| foliage::BinaryOperator::Multiply
=>
{
let parameters = (0..2).map(|_|
{
let variable_declaration = std::rc::Rc::new(
foliage::VariableDeclaration::new("<anonymous>".to_string()));
context.assign_variable_declaration_domain(&variable_declaration,
crate::Domain::Integer);
variable_declaration
})
.collect::<foliage::VariableDeclarations>();
let parameters = std::rc::Rc::new(parameters);
let parameter_1 = &parameters[0];
let parameter_2 = &parameters[1];
let translated_binary_operation = foliage::Term::binary_operation(operator,
Box::new(foliage::Term::variable(&parameter_1)),
Box::new(foliage::Term::variable(&parameter_2)));
let equals = foliage::Formula::equal(
Box::new(foliage::Term::variable(variable_declaration)),
Box::new(translated_binary_operation));
let choose_value_from_left_argument = choose_value_in_term(
binary_operation.left(), &parameter_1, context)?;
let choose_value_from_right_argument = choose_value_in_term(
binary_operation.right(), &parameter_2, context)?;
let and = foliage::Formula::And(vec![Box::new(equals),
Box::new(choose_value_from_left_argument),
Box::new(choose_value_from_right_argument)]);
Ok(foliage::Formula::exists(parameters, Box::new(and)))
},
foliage::BinaryOperator::Divide
| foliage::BinaryOperator::Modulo
=>
{
let parameters = (0..4).map(|_|
{
let variable_declaration = std::rc::Rc::new(
foliage::VariableDeclaration::new("<anonymous>".to_string()));
context.assign_variable_declaration_domain(&variable_declaration,
crate::Domain::Integer);
variable_declaration
})
.collect::<foliage::VariableDeclarations>();
let parameters = std::rc::Rc::new(parameters);
let parameter_i = &parameters[0];
let parameter_j = &parameters[1];
let parameter_q = &parameters[2];
let parameter_r = &parameters[3];
let j_times_q = foliage::Term::multiply(
Box::new(foliage::Term::variable(parameter_j)),
Box::new(foliage::Term::variable(parameter_q)));
let j_times_q_plus_r = foliage::Term::add(Box::new(j_times_q),
Box::new(foliage::Term::variable(parameter_r)));
let i_equals_j_times_q_plus_r = foliage::Formula::equal(
Box::new(foliage::Term::variable(parameter_j)), Box::new(j_times_q_plus_r));
let choose_i_in_t1 = choose_value_in_term(binary_operation.left(), parameter_i,
context)?;
let choose_i_in_t2 = choose_value_in_term(binary_operation.left(), parameter_j,
context)?;
let j_not_equal_to_0 = foliage::Formula::not_equal(
Box::new(foliage::Term::variable(parameter_j)),
Box::new(foliage::Term::integer(0)));
let r_greater_or_equal_to_0 = foliage::Formula::greater_or_equal(
Box::new(foliage::Term::variable(parameter_r)),
Box::new(foliage::Term::integer(0)));
let r_less_than_q = foliage::Formula::less(
Box::new(foliage::Term::variable(parameter_r)),
Box::new(foliage::Term::variable(parameter_q)));
let z_equal_to_q = foliage::Formula::equal(
Box::new(foliage::Term::variable(variable_declaration)),
Box::new(foliage::Term::variable(parameter_q)));
let z_equal_to_r = foliage::Formula::equal(
Box::new(foliage::Term::variable(variable_declaration)),
Box::new(foliage::Term::variable(parameter_r)));
let last_argument = match operator
{
foliage::BinaryOperator::Divide => z_equal_to_q,
foliage::BinaryOperator::Modulo => z_equal_to_r,
_ => return Err(crate::Error::new_logic("unreachable code")),
};
let and = foliage::Formula::and(vec![Box::new(i_equals_j_times_q_plus_r),
Box::new(choose_i_in_t1), Box::new(choose_i_in_t2),
Box::new(j_not_equal_to_0), Box::new(r_greater_or_equal_to_0),
Box::new(r_less_than_q), Box::new(last_argument)]);
Ok(foliage::Formula::exists(parameters, Box::new(and)))
},
foliage::BinaryOperator::Exponentiate =>
Err(crate::Error::new_unsupported_language_feature("exponentiation")),
}
},
clingo::ast::TermType::UnaryOperation(unary_operation) =>
{
match unary_operation.unary_operator()
{
clingo::ast::UnaryOperator::Absolute =>
return Err(crate::Error::new_unsupported_language_feature("absolute value")),
clingo::ast::UnaryOperator::Minus =>
{
let parameter_z_prime = std::rc::Rc::new(foliage::VariableDeclaration::new(
"<anonymous>".to_string()));
context.assign_variable_declaration_domain(&parameter_z_prime,
crate::Domain::Integer);
let negative_z_prime = foliage::Term::negative(Box::new(
foliage::Term::variable(&parameter_z_prime)));
let equals = foliage::Formula::equal(
Box::new(foliage::Term::variable(variable_declaration)),
Box::new(negative_z_prime));
let choose_z_prime_in_t_prime = choose_value_in_term(unary_operation.argument(),
&parameter_z_prime, context)?;
let and = foliage::Formula::and(vec![Box::new(equals),
Box::new(choose_z_prime_in_t_prime)]);
let parameters = std::rc::Rc::new(vec![parameter_z_prime]);
Ok(foliage::Formula::exists(parameters, Box::new(and)))
},
_ => Err(crate::Error::new_not_yet_implemented("todo")),
}
},
clingo::ast::TermType::Interval(interval) =>
{
let parameters = (0..3).map(|_|
{
let variable_declaration = std::rc::Rc::new(
foliage::VariableDeclaration::new("<anonymous>".to_string()));
context.assign_variable_declaration_domain(&variable_declaration,
crate::Domain::Integer);
variable_declaration
})
.collect::<foliage::VariableDeclarations>();
let parameters = std::rc::Rc::new(parameters);
let parameter_i = &parameters[0];
let parameter_j = &parameters[1];
let parameter_k = &parameters[2];
let choose_i_in_t_1 = choose_value_in_term(interval.left(), parameter_i, context)?;
let choose_j_in_t_2 = choose_value_in_term(interval.right(), parameter_j, context)?;
let i_less_than_or_equal_to_k = foliage::Formula::less_or_equal(
Box::new(foliage::Term::variable(parameter_i)),
Box::new(foliage::Term::variable(parameter_k)));
let k_less_than_or_equal_to_j = foliage::Formula::less_or_equal(
Box::new(foliage::Term::variable(parameter_k)),
Box::new(foliage::Term::variable(parameter_j)));
let z_equals_k = foliage::Formula::equal(
Box::new(foliage::Term::variable(variable_declaration)),
Box::new(foliage::Term::variable(parameter_k)));
let and = foliage::Formula::and(vec![Box::new(choose_i_in_t_1),
Box::new(choose_j_in_t_2), Box::new(i_less_than_or_equal_to_k),
Box::new(k_less_than_or_equal_to_j), Box::new(z_equals_k)]);
Ok(foliage::Formula::exists(parameters, Box::new(and)))
},
clingo::ast::TermType::Function(_) =>
Err(crate::Error::new_unsupported_language_feature("symbolic functions")),
clingo::ast::TermType::Pool(_) =>
Err(crate::Error::new_unsupported_language_feature("pools")),
clingo::ast::TermType::ExternalFunction(_) =>
Err(crate::Error::new_unsupported_language_feature("external functions")),
}
}