Files
scryer-prolog/src/prolog/ast.rs
2018-05-09 22:58:23 -06:00

1782 lines
50 KiB
Rust

use prolog::num::bigint::BigInt;
use prolog::num::{Float, ToPrimitive, Zero};
use prolog::num::rational::Ratio;
use prolog::ordered_float::*;
use prolog::tabled_rc::*;
use std::cell::{Cell, RefCell};
use std::cmp::Ordering;
use std::collections::{BTreeSet, HashMap, VecDeque};
use std::fmt;
use std::hash::{Hash, Hasher};
use std::io::Error as IOError;
use std::ops::{Add, AddAssign, Div, Index, IndexMut, Sub, Mul, Neg};
use std::rc::Rc;
use std::str::Utf8Error;
use std::vec::Vec;
pub type Atom = String;
pub type Var = String;
pub type Specifier = u32;
pub const XFX: u32 = 0x0001;
pub const XFY: u32 = 0x0002;
pub const YFX: u32 = 0x0004;
pub const XF: u32 = 0x0010;
pub const YF: u32 = 0x0020;
pub const FX: u32 = 0x0040;
pub const FY: u32 = 0x0080;
pub const DELIMITER: u32 = 0x0100;
pub const TERM: u32 = 0x1000;
pub const LTERM: u32 = 0x3000;
macro_rules! is_term {
($x:expr) => ( ($x & TERM) != 0 )
}
macro_rules! is_lterm {
($x:expr) => ( ($x & LTERM) != 0 )
}
macro_rules! is_op {
($x:expr) => ( $x & (XF | YF | FX | FY | XFX | XFY | YFX) != 0 )
}
macro_rules! is_postfix {
($x:expr) => ( $x & (XF | YF) != 0 )
}
macro_rules! is_infix {
($x:expr) => ( ($x & (XFX | XFY | YFX)) != 0 )
}
macro_rules! is_xfx {
($x:expr) => ( ($x & XFX) != 0 )
}
macro_rules! is_xfy {
($x:expr) => ( ($x & XFY) != 0 )
}
macro_rules! is_yfx {
($x:expr) => ( ($x & YFX) != 0 )
}
macro_rules! is_yf {
($x:expr) => ( ($x & YF) != 0 )
}
macro_rules! is_xf {
($x:expr) => ( ($x & XF) != 0 )
}
macro_rules! is_fx {
($x:expr) => ( ($x & FX) != 0 )
}
macro_rules! is_fy {
($x:expr) => ( ($x & FY) != 0 )
}
macro_rules! prefix {
($x:expr) => ($x & (FX | FY))
}
#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord)]
pub enum GenContext {
Head, Mid(usize), Last(usize) // Mid & Last: chunk_num
}
impl GenContext {
pub fn chunk_num(self) -> usize {
match self {
GenContext::Head => 0,
GenContext::Mid(cn) | GenContext::Last(cn) => cn
}
}
}
pub struct Predicate(pub Vec<PredicateClause>);
impl Predicate {
pub fn clauses(self) -> Vec<PredicateClause> {
self.0
}
}
pub enum PredicateClause {
Fact(Term),
Rule(Rule)
}
impl PredicateClause {
pub fn first_arg(&self) -> Option<&Term> {
match self {
&PredicateClause::Fact(ref term) => term.first_arg(),
&PredicateClause::Rule(ref rule) => rule.head.1.first().map(|bt| bt.as_ref()),
}
}
pub fn arity(&self) -> usize {
match self {
&PredicateClause::Fact(ref term) => term.arity(),
&PredicateClause::Rule(ref rule) => rule.head.1.len()
}
}
pub fn name(&self) -> Option<ClauseName> {
match self {
&PredicateClause::Fact(ref term) => term.name(),
&PredicateClause::Rule(ref rule) => Some(rule.head.0.clone()),
}
}
}
pub type OpDirKey = (ClauseName, Fixity);
// name and fixity -> operator type and precedence.
pub type OpDir = HashMap<OpDirKey, (Specifier, usize, ClauseName)>;
pub type ModuleCodeDir = HashMap<PredicateKey, ModuleCodeIndex>;
pub type CodeDir = HashMap<PredicateKey, CodeIndex>;
pub type TermDir = HashMap<PredicateKey, Predicate>;
pub type PredicateKey = (ClauseName, usize); // name, arity.
pub struct ModuleDecl {
pub name: ClauseName,
pub exports: Vec<PredicateKey>
}
pub struct Module {
pub module_decl: ModuleDecl,
pub code_dir: ModuleCodeDir,
pub op_dir: OpDir
}
impl Module {
pub fn new(module_decl: ModuleDecl) -> Self {
Module { module_decl,
code_dir: ModuleCodeDir::new(),
op_dir: OpDir::new() }
}
}
pub fn as_module_code_dir(code_dir: CodeDir) -> ModuleCodeDir {
code_dir.into_iter()
.map(|(k, code_idx)| {
let (idx, module_name) = code_idx.0.borrow().clone();
(k, ModuleCodeIndex(idx, module_name))
})
.collect()
}
impl SubModuleUser for Module {
fn op_dir(&mut self) -> &mut OpDir {
&mut self.op_dir
}
fn insert_dir_entry(&mut self, name: ClauseName, arity: usize, idx: ModuleCodeIndex) {
self.code_dir.insert((name, arity), idx);
}
}
pub trait SubModuleUser {
fn op_dir(&mut self) -> &mut OpDir;
fn insert_dir_entry(&mut self, ClauseName, usize, ModuleCodeIndex);
// returns true on successful import.
fn import_decl(&mut self, name: ClauseName, arity: usize, submodule: &Module) -> bool {
let name = name.defrock_brackets();
let mut found_op = false;
{
let mut insert_op_dir = |fix| {
if let Some(op_data) = submodule.op_dir.get(&(name.clone(), fix)) {
self.op_dir().insert((name.clone(), fix), op_data.clone());
found_op = true;
}
};
if arity == 1 {
insert_op_dir(Fixity::Pre);
insert_op_dir(Fixity::Post);
} else if arity == 2 {
insert_op_dir(Fixity::In);
}
}
if let Some(code_data) = submodule.code_dir.get(&(name.clone(), arity)) {
self.insert_dir_entry(name, arity, code_data.clone());
true
} else {
found_op
}
}
fn use_qualified_module(&mut self, submodule: &Module, exports: &Vec<PredicateKey>) -> EvalSession
{
for (name, arity) in exports.iter().cloned() {
if !submodule.module_decl.exports.contains(&(name.clone(), arity)) {
continue;
}
if !self.import_decl(name, arity, submodule) {
return EvalSession::from(SessionError::ModuleDoesNotContainExport);
}
}
EvalSession::EntrySuccess
}
fn use_module(&mut self, submodule: &Module) -> EvalSession {
for (name, arity) in submodule.module_decl.exports.iter().cloned() {
if !self.import_decl(name, arity, submodule) {
return EvalSession::from(SessionError::ModuleDoesNotContainExport);
}
}
EvalSession::EntrySuccess
}
}
pub enum Declaration {
Module(ModuleDecl),
Op(OpDecl),
UseModule(ClauseName),
UseQualifiedModule(ClauseName, Vec<PredicateKey>)
}
pub enum TopLevel {
Declaration(Declaration),
Fact(Term),
Predicate(Predicate),
Query(Vec<QueryTerm>),
Rule(Rule)
}
impl TopLevel {
pub fn name(&self) -> Option<ClauseName> {
match self {
&TopLevel::Declaration(_) => None,
&TopLevel::Fact(ref term) => term.name(),
&TopLevel::Predicate(ref clauses) =>
clauses.0.first().and_then(|ref term| term.name()),
&TopLevel::Query(_) => None,
&TopLevel::Rule(Rule { ref head, .. }) =>
Some(head.0.clone())
}
}
pub fn arity(&self) -> usize {
match self {
&TopLevel::Declaration(_) => 0,
&TopLevel::Fact(ref term) => term.arity(),
&TopLevel::Predicate(ref clauses) =>
clauses.0.first().map(|t| t.arity()).unwrap_or(0),
&TopLevel::Query(_) => 0,
&TopLevel::Rule(Rule { ref head, .. }) => head.1.len()
}
}
pub fn as_predicate(self) -> Result<Predicate, TopLevel> {
match self {
TopLevel::Fact(term) => Ok(Predicate(vec![PredicateClause::Fact(term)])),
TopLevel::Rule(rule) => Ok(Predicate(vec![PredicateClause::Rule(rule)])),
TopLevel::Predicate(pred) => Ok(pred),
_ => Err(self)
}
}
}
#[derive(Clone, Copy)]
pub enum Level {
Deep, Root, Shallow
}
impl Level {
pub fn child_level(self) -> Level {
match self {
Level::Root => Level::Shallow,
_ => Level::Deep
}
}
}
#[derive(Clone, Copy, PartialEq, Eq, Hash)]
pub enum RegType {
Perm(usize),
Temp(usize)
}
impl Default for RegType {
fn default() -> Self {
RegType::Temp(0)
}
}
impl RegType {
pub fn reg_num(self) -> usize {
match self {
RegType::Perm(reg_num) | RegType::Temp(reg_num) => reg_num
}
}
pub fn is_perm(self) -> bool {
match self {
RegType::Perm(_) => true,
_ => false
}
}
}
#[derive(PartialEq, Eq, Clone, Copy)]
pub enum VarReg {
ArgAndNorm(RegType, usize),
Norm(RegType)
}
impl VarReg {
pub fn norm(self) -> RegType {
match self {
VarReg::ArgAndNorm(reg, _) | VarReg::Norm(reg) => reg
}
}
}
impl Default for VarReg {
fn default() -> Self {
VarReg::Norm(RegType::default())
}
}
// labeled with chunk numbers.
pub enum VarStatus {
Perm(usize), Temp(usize, TempVarData) // Perm(chunk_num) | Temp(chunk_num, _)
}
pub type OccurrenceSet = BTreeSet<(GenContext, usize)>;
// Perm: 0 initially, a stack register once processed.
// Temp: labeled with chunk_num and temp offset (unassigned if 0).
pub enum VarData {
Perm(usize), Temp(usize, usize, TempVarData)
}
pub struct TempVarData {
pub last_term_arity: usize,
pub use_set: OccurrenceSet,
pub no_use_set: BTreeSet<usize>,
pub conflict_set: BTreeSet<usize>
}
pub type HeapVarDict = HashMap<Rc<Var>, Addr>;
pub type AllocVarDict = HashMap<Rc<Var>, VarData>;
pub enum SessionError {
ImpermissibleEntry(String),
ModuleDoesNotContainExport,
ModuleNotFound,
NamelessEntry,
OpIsInfixAndPostFix,
ParserError(ParserError),
QueryFailure,
QueryFailureWithException(String)
}
pub enum EvalSession {
EntrySuccess,
Error(SessionError),
InitialQuerySuccess(AllocVarDict, HeapVarDict),
SubsequentQuerySuccess,
}
impl From<SessionError> for EvalSession {
fn from(err: SessionError) -> Self {
EvalSession::Error(err)
}
}
impl From<ParserError> for SessionError {
fn from(err: ParserError) -> Self {
SessionError::ParserError(err)
}
}
impl From<ParserError> for EvalSession {
fn from(err: ParserError) -> Self {
EvalSession::from(SessionError::ParserError(err))
}
}
pub struct OpDecl(pub usize, pub Specifier, pub ClauseName);
impl OpDecl {
pub fn submit(&self, module: ClauseName, op_dir: &mut OpDir) -> Result<(), SessionError>
{
let (prec, spec, name) = (self.0, self.1, self.2.clone());
if is_infix!(spec) {
match op_dir.get(&(name.clone(), Fixity::Post)) {
Some(_) => return Err(SessionError::OpIsInfixAndPostFix),
_ => {}
};
}
if is_postfix!(spec) {
match op_dir.get(&(name.clone(), Fixity::In)) {
Some(_) => return Err(SessionError::OpIsInfixAndPostFix),
_ => {}
};
}
if prec > 0 {
match spec {
XFY | XFX | YFX => op_dir.insert((name.clone(), Fixity::In),
(spec, prec, module.clone())),
XF | YF => op_dir.insert((name.clone(), Fixity::Post), (spec, prec, module.clone())),
FX | FY => op_dir.insert((name.clone(), Fixity::Pre), (spec, prec, module.clone())),
_ => None
};
} else {
op_dir.remove(&(name.clone(), Fixity::Pre));
op_dir.remove(&(name.clone(), Fixity::In));
op_dir.remove(&(name.clone(), Fixity::Post));
}
Ok(())
}
}
#[derive(Debug, Clone, Copy)]
pub enum ArithmeticError {
InvalidAtom,
InvalidOp,
InvalidTerm,
UninstantiatedVar
}
#[derive(Debug)]
pub enum ParserError
{
Arithmetic(ArithmeticError),
BackQuotedString,
BuiltInArityMismatch(&'static str),
UnexpectedChar(char),
UnexpectedEOF,
IO(IOError),
ExpectedRel,
InadmissibleFact,
InadmissibleQueryTerm,
IncompleteReduction,
InconsistentEntry,
InvalidModuleDecl,
InvalidModuleExport,
InvalidRuleHead,
InvalidUseModuleDecl,
MissingQuote,
ParseBigInt,
ParseFloat,
Utf8Conversion(Utf8Error)
}
impl From<ArithmeticError> for ParserError {
fn from(err: ArithmeticError) -> ParserError {
ParserError::Arithmetic(err)
}
}
impl From<IOError> for ParserError {
fn from(err: IOError) -> ParserError {
ParserError::IO(err)
}
}
impl From<Utf8Error> for ParserError {
fn from(err: Utf8Error) -> ParserError {
ParserError::Utf8Conversion(err)
}
}
#[derive(Clone, Copy, Eq, Hash, PartialEq)]
pub enum Fixity {
In, Post, Pre
}
#[derive(Clone, Eq, Hash, PartialEq)]
pub enum Constant {
Atom(ClauseName),
Char(char),
Number(Number),
String(Rc<String>),
Usize(usize),
EmptyList
}
impl Constant {
pub fn to_atom(self) -> Option<ClauseName> {
match self {
Constant::Atom(a) => Some(a),
_ => None
}
}
pub fn to_integer(self) -> Option<Rc<BigInt>> {
match self {
Constant::Number(Number::Integer(b)) => Some(b),
_ => None
}
}
}
impl fmt::Display for Constant {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match self {
&Constant::Atom(ref atom) =>
write!(f, "{}", atom),
&Constant::Char(c) =>
write!(f, "'{}'", c as u8),
&Constant::EmptyList =>
write!(f, "[]"),
&Constant::Number(ref n) =>
write!(f, "{}", n),
&Constant::String(ref s) =>
write!(f, "\"{}\"", s),
&Constant::Usize(integer) =>
write!(f, "u{}", integer)
}
}
}
#[derive(PartialEq, Eq, Clone)]
pub enum Term {
AnonVar,
Clause(Cell<RegType>, ClauseName, Vec<Box<Term>>, Option<Fixity>),
Cons(Cell<RegType>, Box<Term>, Box<Term>),
Constant(Cell<RegType>, Constant),
Var(Cell<VarReg>, Rc<Var>)
}
#[derive(Clone, Copy, PartialEq)]
pub enum InlinedClauseType {
CompareNumber(CompareNumberQT, RegType, RegType),
IsAtom(RegType),
IsAtomic(RegType),
IsCompound(RegType),
IsInteger(RegType),
IsRational(RegType),
IsString(RegType),
IsFloat(RegType),
IsNonVar(RegType),
IsVar(RegType),
}
impl InlinedClauseType {
pub fn name(&self) -> &'static str {
match self {
&InlinedClauseType::CompareNumber(qt, ..) => qt.name(),
&InlinedClauseType::IsAtom(..) => "atom",
&InlinedClauseType::IsAtomic(..) => "atomic",
&InlinedClauseType::IsCompound(..) => "compound",
&InlinedClauseType::IsInteger (..) => "integer",
&InlinedClauseType::IsRational(..) => "rational",
&InlinedClauseType::IsString(..) => "string",
&InlinedClauseType::IsFloat (..) => "float",
&InlinedClauseType::IsNonVar(..) => "nonvar",
&InlinedClauseType::IsVar(..) => "var"
}
}
pub fn arity(&self) -> usize {
match self {
&InlinedClauseType::CompareNumber(..) => 2,
&InlinedClauseType::IsAtom(..) => 1,
&InlinedClauseType::IsAtomic(..) => 1,
&InlinedClauseType::IsCompound(..) => 1,
&InlinedClauseType::IsInteger (..) => 1,
&InlinedClauseType::IsRational(..) => 1,
&InlinedClauseType::IsString(..) => 1,
&InlinedClauseType::IsFloat (..) => 1,
&InlinedClauseType::IsNonVar(..) => 1,
&InlinedClauseType::IsVar(..) => 1
}
}
pub fn from(name: &str, arity: usize) -> Option<Self> {
let r1 = temp_v!(1);
let r2 = temp_v!(2);
match (name, arity) {
(">", 2) =>
Some(InlinedClauseType::CompareNumber(CompareNumberQT::GreaterThan, r1, r2)),
("<", 2) =>
Some(InlinedClauseType::CompareNumber(CompareNumberQT::LessThan, r1, r2)),
(">=", 2) =>
Some(InlinedClauseType::CompareNumber(CompareNumberQT::GreaterThanOrEqual,r1, r2)),
("=<", 2) =>
Some(InlinedClauseType::CompareNumber(CompareNumberQT::LessThanOrEqual, r1, r2)),
("=\\=", 2) =>
Some(InlinedClauseType::CompareNumber(CompareNumberQT::NotEqual, r1, r2)),
("=:=", 2) =>
Some(InlinedClauseType::CompareNumber(CompareNumberQT::Equal, r1, r2)),
("atom", 1) => Some(InlinedClauseType::IsAtom(r1)),
("atomic", 1) => Some(InlinedClauseType::IsAtomic(r1)),
("compound", 1) => Some(InlinedClauseType::IsCompound(r1)),
("integer", 1) => Some(InlinedClauseType::IsInteger(r1)),
("rational", 1) => Some(InlinedClauseType::IsRational(r1)),
("string", 1) => Some(InlinedClauseType::IsString(r1)),
("float", 1) => Some(InlinedClauseType::IsFloat(r1)),
("nonvar", 1) => Some(InlinedClauseType::IsNonVar(r1)),
("var", 1) => Some(InlinedClauseType::IsVar(r1)),
_ => None
}
}
}
#[derive(Clone, Copy, PartialEq)]
pub enum CompareNumberQT {
GreaterThan,
LessThan,
GreaterThanOrEqual,
LessThanOrEqual,
NotEqual,
Equal
}
impl CompareNumberQT {
fn name(self) -> &'static str {
match self {
CompareNumberQT::GreaterThan => ">",
CompareNumberQT::LessThan => "<",
CompareNumberQT::GreaterThanOrEqual => ">=",
CompareNumberQT::LessThanOrEqual => "=<",
CompareNumberQT::NotEqual => "=\\=",
CompareNumberQT::Equal => "=:="
}
}
}
#[derive(Clone, Copy, PartialEq)]
pub enum CompareTermQT {
LessThan,
LessThanOrEqual,
Equal,
GreaterThanOrEqual,
GreaterThan,
NotEqual,
}
impl CompareTermQT {
fn name<'a>(self) -> &'a str {
match self {
CompareTermQT::GreaterThan => "@>",
CompareTermQT::LessThan => "@<",
CompareTermQT::GreaterThanOrEqual => "@>=",
CompareTermQT::LessThanOrEqual => "@=<",
CompareTermQT::NotEqual => "\\=@=",
CompareTermQT::Equal => "=@="
}
}
}
// vars of predicate, toplevel offset. Vec<Term> is always a vector
// of vars (we get their adjoining cells this way).
pub type JumpStub = Vec<Term>;
pub enum QueryTerm {
Clause(Cell<RegType>, ClauseType, Vec<Box<Term>>),
BlockedCut, // a cut which is 'blocked by letters', like the P term in P -> Q.
UnblockedCut(Cell<VarReg>),
Jump(JumpStub)
}
impl QueryTerm {
pub fn arity(&self) -> usize {
match self {
&QueryTerm::Clause(_, _, ref subterms) => subterms.len(),
&QueryTerm::BlockedCut | &QueryTerm::UnblockedCut(..) => 0,
&QueryTerm::Jump(ref vars) => vars.len()
}
}
}
pub struct Rule {
pub head: (ClauseName, Vec<Box<Term>>, QueryTerm),
pub clauses: Vec<QueryTerm>
}
#[derive(Copy, Clone, PartialEq)]
pub enum SystemClauseType {
SkipMaxList
}
impl SystemClauseType {
pub fn arity(&self) -> usize {
match self {
&SystemClauseType::SkipMaxList => 4
}
}
pub fn fixity(&self) -> Option<Fixity> {
None
}
pub fn name(&self) -> ClauseName {
match self {
&SystemClauseType::SkipMaxList => clause_name!("$skip_max_list"),
}
}
pub fn from(name: &str, arity: usize) -> Option<SystemClauseType> {
match (name, arity) {
("$skip_max_list", 4) => Some(SystemClauseType::SkipMaxList),
_ => None
}
}
}
#[derive(Copy, Clone, PartialEq)]
pub enum BuiltInClauseType {
AcyclicTerm,
Compare,
CompareTerm(CompareTermQT),
CyclicTerm,
Display,
DuplicateTerm,
Eq,
Functor,
Ground,
Is,
KeySort,
NotEq,
Sort,
System(SystemClauseType)
}
#[derive(Clone)]
pub enum ClauseType {
BuiltIn(BuiltInClauseType),
CallN,
Inlined(InlinedClauseType),
Op(ClauseName, Fixity, CodeIndex),
Named(ClauseName, CodeIndex)
}
#[derive(Clone)]
pub enum ClauseName {
BuiltIn(&'static str),
User(TabledRc<Atom>)
}
impl Hash for ClauseName {
fn hash<H: Hasher>(&self, state: &mut H) {
(*self.as_str()).hash(state)
}
}
impl PartialEq for ClauseName {
fn eq(&self, other: &ClauseName) -> bool {
*self.as_str() == *other.as_str()
}
}
impl Eq for ClauseName {}
impl Ord for ClauseName {
fn cmp(&self, other: &ClauseName) -> Ordering {
(*self.as_str()).cmp(other.as_str())
}
}
impl PartialOrd for ClauseName {
fn partial_cmp(&self, other: &ClauseName) -> Option<Ordering> {
Some(self.cmp(other))
}
}
impl<'a> From<&'a TabledRc<Atom>> for ClauseName {
fn from(name: &'a TabledRc<Atom>) -> ClauseName {
ClauseName::User(name.clone())
}
}
impl ClauseName {
pub fn as_str(&self) -> &str {
match self {
&ClauseName::BuiltIn(s) => s,
&ClauseName::User(ref name) => name.as_ref()
}
}
pub fn defrock_brackets(self) -> Self {
fn defrock_brackets(s: &str) -> &str {
if s.starts_with('(') && s.ends_with(')') {
&s[1 .. s.len() - 1]
} else {
s
}
}
match self {
ClauseName::BuiltIn(s) =>
ClauseName::BuiltIn(defrock_brackets(s)),
ClauseName::User(s) =>
ClauseName::User(tabled_rc!(defrock_brackets(s.as_str()).to_owned(),
s.atom_tbl()))
}
}
}
impl BuiltInClauseType {
fn fixity(&self) -> Option<Fixity> {
match self {
&BuiltInClauseType::Compare | &BuiltInClauseType::CompareTerm(_)
| &BuiltInClauseType::NotEq | &BuiltInClauseType::Is | &BuiltInClauseType::Eq
=> Some(Fixity::In),
_ => None
}
}
pub fn name(&self) -> ClauseName {
match self {
&BuiltInClauseType::AcyclicTerm => clause_name!("acyclic_term"),
&BuiltInClauseType::Compare => clause_name!("compare"),
&BuiltInClauseType::CompareTerm(qt) => clause_name!(qt.name()),
&BuiltInClauseType::CyclicTerm => clause_name!("cyclic_term"),
&BuiltInClauseType::Display => clause_name!("display"),
&BuiltInClauseType::DuplicateTerm => clause_name!("duplicate_term"),
&BuiltInClauseType::Eq => clause_name!("=="),
&BuiltInClauseType::Functor => clause_name!("functor"),
&BuiltInClauseType::Ground => clause_name!("ground"),
&BuiltInClauseType::Is => clause_name!("is"),
&BuiltInClauseType::KeySort => clause_name!("keysort"),
&BuiltInClauseType::NotEq => clause_name!("\\=="),
&BuiltInClauseType::Sort => clause_name!("sort"),
&BuiltInClauseType::System(system) => system.name()
}
}
pub fn arity(&self) -> usize {
match self {
&BuiltInClauseType::AcyclicTerm => 1,
&BuiltInClauseType::Compare => 2,
&BuiltInClauseType::CompareTerm(_) => 2,
&BuiltInClauseType::CyclicTerm => 1,
&BuiltInClauseType::Display => 1,
&BuiltInClauseType::DuplicateTerm => 2,
&BuiltInClauseType::Eq => 2,
&BuiltInClauseType::Functor => 3,
&BuiltInClauseType::Ground => 1,
&BuiltInClauseType::Is => 2,
&BuiltInClauseType::KeySort => 2,
&BuiltInClauseType::NotEq => 2,
&BuiltInClauseType::Sort => 2,
&BuiltInClauseType::System(system) => system.arity()
}
}
pub fn from(name: &str, arity: usize) -> Option<Self> {
match (name, arity) {
("acyclic_term", 1) => Some(BuiltInClauseType::AcyclicTerm),
("compare", 3) => Some(BuiltInClauseType::Compare),
("cyclic_term", 1) => Some(BuiltInClauseType::CyclicTerm),
("@>", 2) => Some(BuiltInClauseType::CompareTerm(CompareTermQT::GreaterThan)),
("@<", 2) => Some(BuiltInClauseType::CompareTerm(CompareTermQT::LessThan)),
("@>=", 2) => Some(BuiltInClauseType::CompareTerm(CompareTermQT::GreaterThanOrEqual)),
("@<=", 2) => Some(BuiltInClauseType::CompareTerm(CompareTermQT::LessThanOrEqual)),
("\\=@=", 2) => Some(BuiltInClauseType::CompareTerm(CompareTermQT::NotEqual)),
("=@=", 2) => Some(BuiltInClauseType::CompareTerm(CompareTermQT::Equal)),
("display", 1) => Some(BuiltInClauseType::Display),
("duplicate_term", 2) => Some(BuiltInClauseType::DuplicateTerm),
("==", 2) => Some(BuiltInClauseType::Eq),
("functor", 3) => Some(BuiltInClauseType::Functor),
("ground", 1) => Some(BuiltInClauseType::Ground),
("is", 2) => Some(BuiltInClauseType::Is),
("keysort", 2) => Some(BuiltInClauseType::KeySort),
("\\==", 2) => Some(BuiltInClauseType::NotEq),
("sort", 2) => Some(BuiltInClauseType::Sort),
_ => SystemClauseType::from(name, arity).map(BuiltInClauseType::System)
}
}
}
impl ClauseType {
pub fn fixity(&self) -> Option<Fixity> {
match self {
&ClauseType::BuiltIn(ref built_in) => built_in.fixity(),
&ClauseType::Inlined(InlinedClauseType::CompareNumber(..)) => Some(Fixity::In),
&ClauseType::Op(_, fixity, _) => Some(fixity),
_ => None
}
}
pub fn name(&self) -> ClauseName {
match self {
&ClauseType::CallN => clause_name!("call"),
&ClauseType::BuiltIn(built_in) => built_in.name(),
&ClauseType::Inlined(inlined) => clause_name!(inlined.name()),
&ClauseType::Op(ref name, ..) => name.clone(),
&ClauseType::Named(ref name, ..) => name.clone(),
}
}
pub fn from(name: ClauseName, arity: usize, fixity: Option<Fixity>) -> Self {
InlinedClauseType::from(name.as_str(), arity)
.map(ClauseType::Inlined)
.unwrap_or_else(|| {
BuiltInClauseType::from(name.as_str(), arity)
.map(ClauseType::BuiltIn)
.unwrap_or_else(|| {
if let Some(fixity) = fixity {
ClauseType::Op(name, fixity, CodeIndex::default())
} else if name.as_str() == "call" {
ClauseType::CallN
} else {
ClauseType::Named(name, CodeIndex::default())
}
})
})
}
}
impl From<InlinedClauseType> for ClauseType {
fn from(inlined_ct: InlinedClauseType) -> Self {
ClauseType::Inlined(inlined_ct)
}
}
#[derive(Clone)]
pub enum TermRef<'a> {
AnonVar(Level),
Cons(Level, &'a Cell<RegType>, &'a Term, &'a Term),
Constant(Level, &'a Cell<RegType>, &'a Constant),
Clause(Level, &'a Cell<RegType>, ClauseType, &'a Vec<Box<Term>>),
Var(Level, &'a Cell<VarReg>, Rc<Var>)
}
impl<'a> TermRef<'a> {
pub fn level(self) -> Level {
match self {
TermRef::AnonVar(lvl)
| TermRef::Cons(lvl, ..)
| TermRef::Constant(lvl, ..)
| TermRef::Var(lvl, ..)
| TermRef::Clause(lvl, ..) => lvl
}
}
}
#[derive(Clone)]
pub enum ChoiceInstruction {
RetryMeElse(usize),
TrustMe,
TryMeElse(usize)
}
#[derive(Clone)]
pub enum CutInstruction {
Cut(RegType),
GetLevel(RegType),
NeckCut
}
#[derive(Clone)]
pub enum IndexedChoiceInstruction {
Retry(usize),
Trust(usize),
Try(usize)
}
impl From<IndexedChoiceInstruction> for Line {
fn from(i: IndexedChoiceInstruction) -> Self {
Line::IndexedChoice(i)
}
}
impl IndexedChoiceInstruction {
pub fn offset(&self) -> usize {
match self {
&IndexedChoiceInstruction::Retry(offset) => offset,
&IndexedChoiceInstruction::Trust(offset) => offset,
&IndexedChoiceInstruction::Try(offset) => offset
}
}
}
#[derive(Clone, PartialEq, Eq, Hash)]
pub enum Number {
Float(OrderedFloat<f64>),
Integer(Rc<BigInt>),
Rational(Rc<Ratio<BigInt>>)
}
impl PartialOrd for Number {
fn partial_cmp(&self, other: &Number) -> Option<Ordering> {
match NumberPair::from(self.clone(), other.clone()) {
NumberPair::Integer(n1, n2) =>
Some(n1.cmp(&n2)),
NumberPair::Float(n1, n2) =>
Some(n1.cmp(&n2)),
NumberPair::Rational(n1, n2) =>
Some(n1.cmp(&n2))
}
}
}
impl Ord for Number {
fn cmp(&self, other: &Number) -> Ordering {
match NumberPair::from(self.clone(), other.clone()) {
NumberPair::Integer(n1, n2) =>
n1.cmp(&n2),
NumberPair::Float(n1, n2) =>
n1.cmp(&n2),
NumberPair::Rational(n1, n2) =>
n1.cmp(&n2)
}
}
}
impl fmt::Display for Number {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match self {
&Number::Float(fl) => write!(f, "{}", fl),
&Number::Integer(ref bi) => write!(f, "{}", bi),
&Number::Rational(ref r) => write!(f, "{}", r)
}
}
}
impl Default for Number {
fn default() -> Self {
Number::Float(OrderedFloat(0f64))
}
}
impl Number {
pub fn is_zero(&self) -> bool {
match self {
&Number::Float(fl) => fl.into_inner().is_zero(),
&Number::Integer(ref bi) => bi.is_zero(),
&Number::Rational(ref r) => r.is_zero()
}
}
pub fn gt(self, n2: Number) -> bool {
match NumberPair::from(self, n2) {
NumberPair::Integer(n1, n2) => n1 > n2,
NumberPair::Float(n1, n2) => n1 > n2,
NumberPair::Rational(n1, n2) => n1 > n2
}
}
pub fn gte(self, n2: Number) -> bool {
match NumberPair::from(self, n2) {
NumberPair::Integer(n1, n2) => n1 >= n2,
NumberPair::Float(n1, n2) => n1 >= n2,
NumberPair::Rational(n1, n2) => n1 >= n2
}
}
pub fn lt(self, n2: Number) -> bool {
match NumberPair::from(self, n2) {
NumberPair::Integer(n1, n2) => n1 < n2,
NumberPair::Float(n1, n2) => n1 < n2,
NumberPair::Rational(n1, n2) => n1 < n2
}
}
pub fn lte(self, n2: Number) -> bool {
match NumberPair::from(self, n2) {
NumberPair::Integer(n1, n2) => n1 <= n2,
NumberPair::Float(n1, n2) => n1 <= n2,
NumberPair::Rational(n1, n2) => n1 <= n2
}
}
pub fn ne(self, n2: Number) -> bool {
match NumberPair::from(self, n2) {
NumberPair::Integer(n1, n2) => n1 != n2,
NumberPair::Float(n1, n2) => n1 != n2,
NumberPair::Rational(n1, n2) => n1 != n2
}
}
pub fn eq(self, n2: Number) -> bool {
match NumberPair::from(self, n2) {
NumberPair::Integer(n1, n2) => n1 == n2,
NumberPair::Float(n1, n2) => n1 == n2,
NumberPair::Rational(n1, n2) => n1 == n2
}
}
}
pub enum NumberPair {
Float(OrderedFloat<f64>, OrderedFloat<f64>),
Integer(Rc<BigInt>, Rc<BigInt>),
Rational(Rc<Ratio<BigInt>>, Rc<Ratio<BigInt>>)
}
impl NumberPair {
fn flip(self) -> NumberPair {
match self {
NumberPair::Float(f1, f2) => NumberPair::Float(f2, f1),
NumberPair::Integer(n1, n2) => NumberPair::Integer(n2, n1),
NumberPair::Rational(r1, r2) => NumberPair::Rational(r2, r1)
}
}
fn integer_float_pair(n1: Rc<BigInt>, n2: OrderedFloat<f64>) -> NumberPair {
match n1.to_f64() {
Some(f1) => NumberPair::Float(OrderedFloat(f1), n2),
None => if let Some(r) = Ratio::from_float(n2.into_inner()) {
NumberPair::Rational(Rc::new(Ratio::from_integer((*n1).clone())),
Rc::new(r))
} else if n2.into_inner().is_sign_positive() {
NumberPair::Float(OrderedFloat(f64::infinity()),
OrderedFloat(f64::infinity()))
} else {
NumberPair::Float(OrderedFloat(f64::neg_infinity()),
OrderedFloat(f64::neg_infinity()))
}
}
}
fn float_rational_pair(n1: OrderedFloat<f64>, n2: Rc<Ratio<BigInt>>) -> NumberPair {
match (n2.numer().to_f64(), n2.denom().to_f64()) {
(Some(num), Some(denom)) =>
NumberPair::Float(n1, OrderedFloat(num / denom)),
_ => if let Some(r) = Ratio::from_float(n1.into_inner()) {
NumberPair::Rational(Rc::new(r), n2)
} else if n1.into_inner().is_sign_positive() {
NumberPair::Float(OrderedFloat(f64::infinity()),
OrderedFloat(f64::infinity()))
} else {
NumberPair::Float(OrderedFloat(f64::neg_infinity()),
OrderedFloat(f64::neg_infinity()))
}
}
}
pub fn from(n1: Number, n2: Number) -> NumberPair
{
match (n1, n2) {
(Number::Integer(n1), Number::Integer(n2)) =>
NumberPair::Integer(n1, n2),
(Number::Float(n1), Number::Float(n2)) =>
NumberPair::Float(n1, n2),
(Number::Rational(n1), Number::Rational(n2)) =>
NumberPair::Rational(n1, n2),
(Number::Integer(n1), Number::Float(n2)) =>
Self::integer_float_pair(n1, n2),
(Number::Float(n1), Number::Integer(n2)) =>
Self::integer_float_pair(n2, n1).flip(),
(Number::Float(n1), Number::Rational(n2)) =>
Self::float_rational_pair(n1, n2),
(Number::Rational(n1), Number::Float(n2)) =>
Self::float_rational_pair(n2, n1).flip(),
(Number::Rational(n1), Number::Integer(n2)) =>
NumberPair::Rational(n1, Rc::new(Ratio::from_integer((*n2).clone()))),
(Number::Integer(n1), Number::Rational(n2)) =>
NumberPair::Rational(Rc::new(Ratio::from_integer((*n1).clone())), n2)
}
}
}
impl Add<Number> for Number {
type Output = Number;
fn add(self, rhs: Number) -> Self::Output {
match NumberPair::from(self, rhs) {
NumberPair::Float(f1, f2) =>
Number::Float(OrderedFloat(f1.into_inner() + f2.into_inner())),
NumberPair::Integer(n1, n2) =>
Number::Integer(Rc::new(&*n1 + &*n2)),
NumberPair::Rational(r1, r2) =>
Number::Rational(Rc::new(&*r1 + &*r2))
}
}
}
impl Sub<Number> for Number {
type Output = Number;
fn sub(self, rhs: Number) -> Self::Output {
match NumberPair::from(self, rhs) {
NumberPair::Float(f1, f2) =>
Number::Float(OrderedFloat(f1.into_inner() - f2.into_inner())),
NumberPair::Integer(n1, n2) =>
Number::Integer(Rc::new(&*n1 - &*n2)),
NumberPair::Rational(r1, r2) =>
Number::Rational(Rc::new(&*r1 - &*r2))
}
}
}
impl Mul<Number> for Number {
type Output = Number;
fn mul(self, rhs: Number) -> Self::Output {
match NumberPair::from(self, rhs) {
NumberPair::Float(f1, f2) =>
Number::Float(OrderedFloat(f1.into_inner() * f2.into_inner())),
NumberPair::Integer(n1, n2) =>
Number::Integer(Rc::new(&*n1 * &*n2)),
NumberPair::Rational(r1, r2) =>
Number::Rational(Rc::new(&*r1 * &*r2))
}
}
}
impl Div<Number> for Number {
type Output = Number;
fn div(self, rhs: Number) -> Self::Output {
match NumberPair::from(self, rhs) {
NumberPair::Float(f1, f2) =>
Number::Float(OrderedFloat(f1.into_inner() / f2.into_inner())),
NumberPair::Integer(n1, n2) =>
match n1.to_f64() {
Some(f1) => if let Some(f2) = n2.to_f64() {
Number::Float(OrderedFloat(f1 / f2))
} else {
let r1 = Ratio::from_integer((*n1).clone());
let r2 = Ratio::from_integer((*n2).clone());
Number::Rational(Rc::new(r1 / r2))
},
None => {
let r1 = Ratio::from_integer((*n1).clone());
let r2 = Ratio::from_integer((*n2).clone());
Number::Rational(Rc::new(r1 / r2))
},
},
NumberPair::Rational(r1, r2) =>
Number::Rational(Rc::new(&*r1 / &*r2))
}
}
}
impl Neg for Number {
type Output = Number;
fn neg(self) -> Self::Output {
match self {
Number::Integer(n) => Number::Integer(Rc::new(-&*n)),
Number::Float(f) => Number::Float(OrderedFloat(-1.0 * f.into_inner())),
Number::Rational(r) => Number::Rational(Rc::new(- &*r))
}
}
}
#[derive(Clone)]
pub enum ArithmeticTerm {
Reg(RegType),
Interm(usize),
Number(Number)
}
impl ArithmeticTerm {
pub fn interm_or(&self, interm: usize) -> usize {
if let &ArithmeticTerm::Interm(interm) = self {
interm
} else {
interm
}
}
}
#[derive(Clone)]
pub enum ArithmeticInstruction {
Add(ArithmeticTerm, ArithmeticTerm, usize),
Sub(ArithmeticTerm, ArithmeticTerm, usize),
Mul(ArithmeticTerm, ArithmeticTerm, usize),
IDiv(ArithmeticTerm, ArithmeticTerm, usize),
FIDiv(ArithmeticTerm, ArithmeticTerm, usize),
RDiv(ArithmeticTerm, ArithmeticTerm, usize),
Div(ArithmeticTerm, ArithmeticTerm, usize),
Shl(ArithmeticTerm, ArithmeticTerm, usize),
Shr(ArithmeticTerm, ArithmeticTerm, usize),
Xor(ArithmeticTerm, ArithmeticTerm, usize),
And(ArithmeticTerm, ArithmeticTerm, usize),
Or(ArithmeticTerm, ArithmeticTerm, usize),
Mod(ArithmeticTerm, ArithmeticTerm, usize),
Rem(ArithmeticTerm, ArithmeticTerm, usize),
Neg(ArithmeticTerm, usize)
}
#[derive(Clone)]
pub enum BuiltInInstruction {
CleanUpBlock,
CompareNumber(CompareNumberQT, ArithmeticTerm, ArithmeticTerm),
DefaultRetryMeElse(usize),
DefaultSetCutPoint(RegType),
DefaultTrustMe,
EraseBall,
Fail,
GetArg(bool), // last call.
GetBall,
GetCurrentBlock,
GetCutPoint(RegType),
InferenceLevel(RegType, RegType),
InstallCleaner,
InstallInferenceCounter(RegType, RegType, RegType),
InstallNewBlock,
RemoveCallPolicyCheck,
RemoveInferenceCounter(RegType, RegType),
ResetBlock,
RestoreCutPolicy,
SetBall,
SetCutPoint(RegType),
Succeed,
Unify,
UnwindStack
}
#[derive(Clone)]
pub enum ControlInstruction {
Allocate(usize), // num_frames.
CallClause(ClauseType, usize, usize, bool), // name, arity, perm_vars after threshold, last call.
CheckCpExecute,
Deallocate,
GetCleanerCall,
Goto(usize, usize, bool), // p, arity, last call.
IsClause(bool, RegType, ArithmeticTerm), // last call, register of var, term.
JmpBy(usize, usize, usize, bool), // arity, global_offset, perm_vars after threshold, last call.
Proceed
}
impl ControlInstruction {
pub fn is_jump_instr(&self) -> bool {
match self {
&ControlInstruction::CallClause(..) => true,
&ControlInstruction::GetCleanerCall => true,
&ControlInstruction::Goto(..) => true,
&ControlInstruction::IsClause(..) => true,
&ControlInstruction::JmpBy(..) => true,
_ => false
}
}
}
#[derive(Clone)]
pub enum IndexingInstruction {
SwitchOnTerm(usize, usize, usize, usize),
SwitchOnConstant(usize, HashMap<Constant, usize>),
SwitchOnStructure(usize, HashMap<(ClauseName, usize), usize>)
}
impl From<IndexingInstruction> for Line {
fn from(i: IndexingInstruction) -> Self {
Line::Indexing(i)
}
}
#[derive(Clone)]
pub enum FactInstruction {
GetConstant(Level, Constant, RegType),
GetList(Level, RegType),
GetStructure(ClauseType, usize, RegType),
GetValue(RegType, usize),
GetVariable(RegType, usize),
UnifyConstant(Constant),
UnifyLocalValue(RegType),
UnifyVariable(RegType),
UnifyValue(RegType),
UnifyVoid(usize)
}
#[derive(Clone)]
pub enum QueryInstruction {
GetVariable(RegType, usize),
PutConstant(Level, Constant, RegType),
PutList(Level, RegType),
PutStructure(ClauseType, usize, RegType),
PutUnsafeValue(usize, usize),
PutValue(RegType, usize),
PutVariable(RegType, usize),
SetConstant(Constant),
SetLocalValue(RegType),
SetVariable(RegType),
SetValue(RegType),
SetVoid(usize)
}
pub type CompiledFact = Vec<FactInstruction>;
pub type CompiledQuery = Vec<QueryInstruction>;
#[derive(Clone)]
pub enum Line {
Arithmetic(ArithmeticInstruction),
BuiltIn(BuiltInInstruction),
Choice(ChoiceInstruction),
Control(ControlInstruction),
Cut(CutInstruction),
Fact(CompiledFact),
Indexing(IndexingInstruction),
IndexedChoice(IndexedChoiceInstruction),
Query(CompiledQuery)
}
pub type ThirdLevelIndex = Vec<IndexedChoiceInstruction>;
pub type Code = Vec<Line>;
pub type CodeDeque = VecDeque<Line>;
#[derive(Clone, PartialEq, Eq, Hash)]
pub enum Addr {
Con(Constant),
Lis(usize),
HeapCell(usize),
StackCell(usize, usize),
Str(usize)
}
impl Addr {
pub fn is_ref(&self) -> bool {
match self {
&Addr::HeapCell(_) | &Addr::StackCell(_, _) => true,
_ => false
}
}
pub fn as_var(&self) -> Option<Ref> {
match self {
&Addr::HeapCell(hc) => Some(Ref::HeapCell(hc)),
&Addr::StackCell(fr, sc) => Some(Ref::StackCell(fr, sc)),
_ => None
}
}
pub fn is_protected(&self, e: usize) -> bool {
match self {
&Addr::StackCell(fr, _) if fr > e => false,
_ => true
}
}
}
impl Add<usize> for Addr {
type Output = Addr;
fn add(self, rhs: usize) -> Self::Output {
match self {
Addr::Lis(a) => Addr::Lis(a + rhs),
Addr::HeapCell(hc) => Addr::HeapCell(hc + rhs),
Addr::Str(s) => Addr::Str(s + rhs),
_ => self
}
}
}
impl Sub<usize> for Addr {
type Output = Addr;
fn sub(self, rhs: usize) -> Self::Output {
match self {
Addr::Lis(a) => Addr::Lis(a - rhs),
Addr::HeapCell(hc) => Addr::HeapCell(hc - rhs),
Addr::Str(s) => Addr::Str(s - rhs),
_ => self
}
}
}
impl From<Ref> for Addr {
fn from(r: Ref) -> Self {
match r {
Ref::HeapCell(hc) => Addr::HeapCell(hc),
Ref::StackCell(fr, sc) => Addr::StackCell(fr, sc)
}
}
}
#[derive(Clone, Copy, Hash, Eq, PartialEq)]
pub enum Ref {
HeapCell(usize),
StackCell(usize, usize)
}
#[derive(Clone, PartialEq)]
pub enum HeapCellValue {
Addr(Addr),
NamedStr(usize, ClauseName, Option<Fixity>), // arity, name, fixity if it has one.
}
impl HeapCellValue {
pub fn as_addr(&self, focus: usize) -> Addr {
match self {
&HeapCellValue::Addr(ref a) => a.clone(),
&HeapCellValue::NamedStr(_, _, _) => Addr::Str(focus)
}
}
}
#[derive(Clone, Copy, PartialEq)]
pub enum IndexPtr {
Undefined, Index(usize)
}
#[derive(Clone)]
pub struct CodeIndex(pub Rc<RefCell<(IndexPtr, ClauseName)>>);
#[derive(Clone)]
pub struct ModuleCodeIndex(pub IndexPtr, pub ClauseName);
impl From<ModuleCodeIndex> for CodeIndex {
fn from(value: ModuleCodeIndex) -> Self {
CodeIndex(Rc::new(RefCell::new((value.0, value.1))))
}
}
impl Default for CodeIndex {
fn default() -> Self {
CodeIndex(Rc::new(RefCell::new((IndexPtr::Undefined, clause_name!("")))))
}
}
impl From<(usize, ClauseName)> for CodeIndex {
fn from(value: (usize, ClauseName)) -> Self {
CodeIndex(Rc::new(RefCell::new((IndexPtr::Index(value.0), value.1))))
}
}
#[derive(Clone, PartialEq)]
pub enum CodePtr {
BuiltInClause(BuiltInClauseType, LocalCodePtr), // local is the successor call.
CallN(usize, LocalCodePtr), // the arity of the call, successor call.
Local(LocalCodePtr)
}
impl CodePtr {
pub fn local(&self) -> LocalCodePtr {
match self {
&CodePtr::BuiltInClause(_, ref local)
| &CodePtr::CallN(_, ref local)
| &CodePtr::Local(ref local) => local.clone()
}
}
}
#[derive(Clone, PartialEq)]
pub enum LocalCodePtr {
DirEntry(usize, ClauseName), // offset, resident module name.
TopLevel(usize, usize) // chunk_num, offset.
}
impl LocalCodePtr {
pub fn module_name(&self) -> ClauseName {
match self {
&LocalCodePtr::DirEntry(_, ref name) => name.clone(),
_ => ClauseName::BuiltIn("user")
}
}
pub fn assign_if_local(&mut self, cp: CodePtr) {
match cp {
CodePtr::Local(local) => *self = local,
_ => {}
}
}
}
impl PartialOrd<CodePtr> for CodePtr {
fn partial_cmp(&self, other: &CodePtr) -> Option<Ordering> {
match (self, other) {
(&CodePtr::Local(ref l1), &CodePtr::Local(ref l2)) => l1.partial_cmp(l2),
_ => Some(Ordering::Greater)
}
}
}
impl PartialOrd<LocalCodePtr> for LocalCodePtr {
fn partial_cmp(&self, other: &LocalCodePtr) -> Option<Ordering> {
match (self, other) {
(&LocalCodePtr::DirEntry(p1, _), &LocalCodePtr::DirEntry(p2, _)) =>
p1.partial_cmp(&p2),
(&LocalCodePtr::DirEntry(..), &LocalCodePtr::TopLevel(_, _)) =>
Some(Ordering::Less),
(&LocalCodePtr::TopLevel(_, p1), &LocalCodePtr::TopLevel(_, ref p2)) =>
p1.partial_cmp(p2),
_ => Some(Ordering::Greater)
}
}
}
impl Default for CodePtr {
fn default() -> Self {
CodePtr::Local(LocalCodePtr::default())
}
}
impl Default for LocalCodePtr {
fn default() -> Self {
LocalCodePtr::TopLevel(0, 0)
}
}
impl Add<usize> for LocalCodePtr {
type Output = LocalCodePtr;
fn add(self, rhs: usize) -> Self::Output {
match self {
LocalCodePtr::DirEntry(p, name) => LocalCodePtr::DirEntry(p + rhs, name),
LocalCodePtr::TopLevel(cn, p) => LocalCodePtr::TopLevel(cn, p + rhs)
}
}
}
impl AddAssign<usize> for LocalCodePtr {
fn add_assign(&mut self, rhs: usize) {
match self {
&mut LocalCodePtr::DirEntry(ref mut p, _) |
&mut LocalCodePtr::TopLevel(_, ref mut p) => *p += rhs
}
}
}
impl Add<usize> for CodePtr {
type Output = CodePtr;
fn add(self, rhs: usize) -> Self::Output {
match self {
CodePtr::Local(local) => CodePtr::Local(local + rhs),
CodePtr::BuiltInClause(_, local) => CodePtr::Local(local + rhs),
CodePtr::CallN(_, local) => CodePtr::Local(local + rhs),
}
}
}
impl AddAssign<usize> for CodePtr {
fn add_assign(&mut self, rhs: usize) {
match self {
&mut CodePtr::Local(ref mut local) => *local += rhs,
_ => *self = CodePtr::Local(self.local() + rhs)
}
}
}
pub struct Heap {
heap: Vec<HeapCellValue>,
pub h: usize
}
impl Heap {
pub fn with_capacity(cap: usize) -> Self {
Heap { heap: Vec::with_capacity(cap), h: 0 }
}
pub fn push(&mut self, val: HeapCellValue) {
self.heap.push(val);
self.h += 1;
}
pub fn truncate(&mut self, h: usize) {
self.h = h;
self.heap.truncate(h);
}
pub fn len(&self) -> usize {
self.heap.len()
}
pub fn append(&mut self, vals: Vec<HeapCellValue>) {
let n = vals.len();
self.heap.extend(vals.into_iter());
self.h += n;
}
pub fn clear(&mut self) {
self.heap.clear();
self.h = 0;
}
}
impl Index<usize> for Heap {
type Output = HeapCellValue;
fn index(&self, index: usize) -> &Self::Output {
&self.heap[index]
}
}
impl IndexMut<usize> for Heap {
fn index_mut(&mut self, index: usize) -> &mut Self::Output {
&mut self.heap[index]
}
}
pub type Registers = Vec<Addr>;
impl Term {
pub fn to_constant(self) -> Option<Constant> {
match self {
Term::Constant(_, c) => Some(c),
_ => None
}
}
pub fn first_arg(&self) -> Option<&Term> {
match self {
&Term::Clause(_, _, ref terms, _) =>
terms.first().map(|bt| bt.as_ref()),
_ => None
}
}
pub fn name(&self) -> Option<ClauseName> {
match self {
&Term::Constant(_, Constant::Atom(ref atom))
| &Term::Clause(_, ref atom, ..) => Some(atom.clone()),
_ => None
}
}
pub fn arity(&self) -> usize {
match self {
&Term::Clause(_, _, ref child_terms, ..) => child_terms.len(),
_ => 0
}
}
}
pub enum TermIterState<'a> {
AnonVar(Level),
Constant(Level, &'a Cell<RegType>, &'a Constant),
Clause(Level, usize, &'a Cell<RegType>, ClauseType, &'a Vec<Box<Term>>),
InitialCons(Level, &'a Cell<RegType>, &'a Term, &'a Term),
FinalCons(Level, &'a Cell<RegType>, &'a Term, &'a Term),
Var(Level, &'a Cell<VarReg>, Rc<Var>)
}
impl<'a> TermIterState<'a> {
pub fn subterm_to_state(lvl: Level, term: &'a Term) -> TermIterState<'a> {
match term {
&Term::AnonVar =>
TermIterState::AnonVar(lvl),
&Term::Clause(ref cell, ref name, ref subterms, fixity) => {
let ct = if let Some(fixity) = fixity {
ClauseType::Op(name.clone(), fixity, CodeIndex::default())
} else {
ClauseType::Named(name.clone(), CodeIndex::default())
};
TermIterState::Clause(lvl, 0, cell, ct, subterms)
},
&Term::Cons(ref cell, ref head, ref tail) =>
TermIterState::InitialCons(lvl, cell, head.as_ref(), tail.as_ref()),
&Term::Constant(ref cell, ref constant) =>
TermIterState::Constant(lvl, cell, constant),
&Term::Var(ref cell, ref var) =>
TermIterState::Var(lvl, cell, (*var).clone())
}
}
}