anthem-rs/src/translate/common.rs

94 lines
3.4 KiB
Rust

pub fn translate_comparison_operator(comparison_operator: clingo::ast::ComparisonOperator)
-> foliage::ComparisonOperator
{
match comparison_operator
{
clingo::ast::ComparisonOperator::GreaterThan
=> foliage::ComparisonOperator::Greater,
clingo::ast::ComparisonOperator::LessThan
=> foliage::ComparisonOperator::Less,
clingo::ast::ComparisonOperator::LessEqual
=> foliage::ComparisonOperator::LessOrEqual,
clingo::ast::ComparisonOperator::GreaterEqual
=> foliage::ComparisonOperator::GreaterOrEqual,
clingo::ast::ComparisonOperator::NotEqual
=> foliage::ComparisonOperator::NotEqual,
clingo::ast::ComparisonOperator::Equal
=> foliage::ComparisonOperator::Equal,
}
}
pub fn choose_value_in_primitive(term: Box<foliage::Term>,
variable_declaration: &std::rc::Rc<foliage::VariableDeclaration>)
-> foliage::Comparison
{
let variable = foliage::Variable
{
declaration: std::rc::Rc::clone(variable_declaration),
};
foliage::Comparison
{
operator: foliage::ComparisonOperator::Equal,
left: Box::new(foliage::Term::Variable(variable)),
right: term,
}
}
pub fn choose_value_in_term<F>(term: &clingo::ast::Term,
variable_declaration: &std::rc::Rc<foliage::VariableDeclaration>,
mut find_or_create_function_declaration: F)
-> Result<foliage::Formula, crate::Error>
where
F: FnMut(&str, usize) -> std::rc::Rc<foliage::FunctionDeclaration>
{
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(foliage::Formula::Comparison(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(foliage::Formula::Comparison(choose_value_in_primitive(
Box::new(foliage::Term::SpecialInteger(foliage::SpecialInteger::Infimum)),
variable_declaration))),
clingo::SymbolType::Supremum => Ok(foliage::Formula::Comparison(choose_value_in_primitive(
Box::new(foliage::Term::SpecialInteger(foliage::SpecialInteger::Supremum)),
variable_declaration))),
clingo::SymbolType::String => Ok(foliage::Formula::Comparison(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 = find_or_create_function_declaration(constant_name, 0);
let function = foliage::Term::Function(foliage::Function
{
declaration: constant_declaration,
arguments: vec![],
});
Ok(foliage::Formula::Comparison(choose_value_in_primitive(Box::new(function), variable_declaration)))
}
},
_ => Ok(foliage::Formula::Boolean(false))
}
}