1285 lines
35 KiB
Rust
1285 lines
35 KiB
Rust
use prolog::num::bigint::BigInt;
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use prolog::num::{Float, ToPrimitive, Zero};
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use prolog::num::rational::Ratio;
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use prolog::ordered_float::*;
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use prolog::tabled_rc::*;
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use std::cell::Cell;
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use std::cmp::Ordering;
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use std::collections::{HashMap, VecDeque};
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use std::fmt;
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use std::io::Error as IOError;
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use std::num::{ParseFloatError};
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use std::ops::{Add, AddAssign, Div, Index, IndexMut, Sub, Mul, Neg};
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use std::rc::Rc;
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use std::str::Utf8Error;
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use std::vec::Vec;
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pub const LEXER_BUF_SIZE: usize = 4096;
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pub type Atom = String;
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pub type Var = String;
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#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord)]
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pub enum GenContext {
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Head, Mid(usize), Last(usize) // Mid & Last: chunk_num
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}
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impl GenContext {
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pub fn chunk_num(self) -> usize {
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match self {
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GenContext::Head => 0,
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GenContext::Mid(cn) | GenContext::Last(cn) => cn
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}
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}
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}
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pub type Predicate = Vec<PredicateClause>;
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pub enum PredicateClause {
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Fact(Term),
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Rule(Rule)
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}
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impl PredicateClause {
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pub fn first_arg(&self) -> Option<&Term> {
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match self {
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&PredicateClause::Fact(ref term) => term.first_arg(),
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&PredicateClause::Rule(ref rule) =>
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if let &QueryTerm::Term(ref term) = &rule.head.0 {
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term.first_arg()
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} else {
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None
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}
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}
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}
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pub fn arity(&self) -> usize {
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match self {
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&PredicateClause::Fact(ref term) => term.arity(),
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&PredicateClause::Rule(ref rule) => rule.head.0.arity()
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}
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}
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pub fn name(&self) -> Option<TabledRc<Atom>> {
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match self {
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&PredicateClause::Fact(ref term) => term.name(),
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&PredicateClause::Rule(ref rule) =>
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if let &QueryTerm::Term(ref term) = &rule.head.0 {
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term.name()
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} else {
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None
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}
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}
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}
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}
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pub enum Declaration {
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Op(usize, Specifier, TabledRc<Atom>)
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}
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pub enum TopLevel {
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Declaration(Declaration),
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Fact(Term),
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Predicate(Predicate),
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Query(Vec<QueryTerm>),
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Rule(Rule)
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}
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impl TopLevel {
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pub fn name(&self) -> Option<TabledRc<Atom>> {
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match self {
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&TopLevel::Declaration(_) => None,
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&TopLevel::Fact(ref term) => term.name(),
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&TopLevel::Predicate(ref clauses) =>
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if let Some(ref term) = clauses.first() {
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term.name()
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} else {
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None
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},
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&TopLevel::Query(_) => None,
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&TopLevel::Rule(Rule { head: (QueryTerm::Term(ref term), _), .. }) =>
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match term {
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&Term::Clause(_, ref name, ..)
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| &Term::Constant(_, Constant::Atom(ref name)) =>
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Some(name.clone()),
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_ =>
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None
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},
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_ => None
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}
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}
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pub fn arity(&self) -> usize {
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match self {
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&TopLevel::Declaration(_) => 0,
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&TopLevel::Fact(ref term) => term.arity(),
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&TopLevel::Predicate(ref clauses) =>
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clauses.first().map(|t| t.arity()).unwrap_or(0),
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&TopLevel::Query(_) => 0,
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&TopLevel::Rule(Rule { head: (ref qt, _), ..}) => qt.arity(),
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}
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}
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}
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#[derive(Clone, Copy)]
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pub enum Level {
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Deep, Shallow
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}
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#[derive(Clone, Copy, PartialEq, Eq, Hash)]
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pub enum RegType {
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Perm(usize),
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Temp(usize)
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}
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impl Default for RegType {
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fn default() -> Self {
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RegType::Temp(0)
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}
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}
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impl RegType {
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pub fn reg_num(self) -> usize {
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match self {
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RegType::Perm(reg_num) | RegType::Temp(reg_num) => reg_num
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}
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}
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pub fn is_perm(self) -> bool {
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match self {
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RegType::Perm(_) => true,
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_ => false
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}
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}
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}
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#[derive(PartialEq, Eq, Clone, Copy)]
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pub enum VarReg {
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ArgAndNorm(RegType, usize),
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Norm(RegType)
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}
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impl VarReg {
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pub fn norm(self) -> RegType {
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match self {
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VarReg::ArgAndNorm(reg, _) | VarReg::Norm(reg) => reg
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}
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}
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}
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impl Default for VarReg {
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fn default() -> Self {
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VarReg::Norm(RegType::default())
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}
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}
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pub type Specifier = u32;
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pub const XFX: u32 = 0x0001;
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pub const XFY: u32 = 0x0002;
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pub const YFX: u32 = 0x0004;
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pub const XF: u32 = 0x0010;
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pub const YF: u32 = 0x0020;
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pub const FX: u32 = 0x0040;
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pub const FY: u32 = 0x0080;
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pub const DELIMITER: u32 = 0x0100;
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pub const TERM: u32 = 0x1000;
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pub const LTERM: u32 = 0x3000;
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macro_rules! is_term {
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($x:expr) => ( ($x & TERM) != 0 )
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}
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macro_rules! is_lterm {
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($x:expr) => ( ($x & LTERM) != 0 )
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}
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macro_rules! is_op {
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($x:expr) => ( $x & (XF | YF | FX | FY | XFX | XFY | YFX) != 0 )
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}
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macro_rules! is_postfix {
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($x:expr) => ( $x & (XF | YF) != 0 )
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}
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macro_rules! is_infix {
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($x:expr) => ( ($x & (XFX | XFY | YFX)) != 0 )
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}
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macro_rules! is_xfx {
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($x:expr) => ( ($x & XFX) != 0 )
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}
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macro_rules! is_xfy {
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($x:expr) => ( ($x & XFY) != 0 )
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}
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macro_rules! is_yfx {
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($x:expr) => ( ($x & YFX) != 0 )
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}
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macro_rules! is_yf {
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($x:expr) => ( ($x & YF) != 0 )
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}
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macro_rules! is_xf {
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($x:expr) => ( ($x & XF) != 0 )
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}
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macro_rules! is_fx {
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($x:expr) => ( ($x & FX) != 0 )
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}
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macro_rules! is_fy {
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($x:expr) => ( ($x & FY) != 0 )
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}
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macro_rules! prefix {
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($x:expr) => ($x & (FX | FY))
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}
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#[derive(Debug, Clone, Copy)]
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pub enum ArithmeticError {
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InvalidAtom,
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InvalidOp,
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InvalidTerm,
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UninstantiatedVar
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}
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/* 'TokenTooLong' is hard to detect reliably if we don't process the
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input one character at a time. It would be easy to detect if the regex
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library supported matching on iterator inputs, but it currently does
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not. This is fine, mostly; the typical Prolog program will not contain
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tokens exceeding 4096 chars in length. */
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#[derive(Debug)]
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pub enum ParserError
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{
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Arithmetic(ArithmeticError),
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BuiltInArityMismatch(&'static str),
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UnexpectedEOF,
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FailedMatch(String),
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IO(IOError),
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ExpectedRel,
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InadmissibleFact,
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InadmissibleQueryTerm,
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IncompleteReduction,
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InconsistentEntry, // was InconsistentDeclaration.
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InvalidRuleHead,
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ParseBigInt,
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ParseFloat(ParseFloatError),
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// TokenTooLong,
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Utf8Conversion(Utf8Error)
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}
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impl From<ArithmeticError> for ParserError {
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fn from(err: ArithmeticError) -> ParserError {
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ParserError::Arithmetic(err)
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}
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}
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impl From<IOError> for ParserError {
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fn from(err: IOError) -> ParserError {
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ParserError::IO(err)
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}
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}
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impl From<Utf8Error> for ParserError {
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fn from(err: Utf8Error) -> ParserError {
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ParserError::Utf8Conversion(err)
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}
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}
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impl From<ParseFloatError> for ParserError {
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fn from(err: ParseFloatError) -> ParserError {
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ParserError::ParseFloat(err)
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}
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}
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#[derive(Clone, Copy, Eq, Hash, PartialEq)]
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pub enum Fixity {
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In, Post, Pre
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}
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#[derive(Clone, Eq, Hash, PartialEq)]
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pub enum Constant {
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Atom(TabledRc<Atom>),
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Number(Number),
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String(Rc<String>),
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Usize(usize),
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EmptyList
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}
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impl fmt::Display for Constant {
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fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
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match self {
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&Constant::Atom(ref atom) =>
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write!(f, "{}", atom),
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&Constant::EmptyList =>
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write!(f, "[]"),
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&Constant::Number(ref n) =>
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write!(f, "{}", n),
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&Constant::String(ref s) =>
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write!(f, "{}", s),
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&Constant::Usize(integer) =>
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write!(f, "u{}", integer)
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}
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}
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}
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#[derive(PartialEq, Eq, Clone)]
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pub enum Term {
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AnonVar,
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Clause(Cell<RegType>, TabledRc<Atom>, Vec<Box<Term>>, Option<Fixity>),
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Cons(Cell<RegType>, Box<Term>, Box<Term>),
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Constant(Cell<RegType>, Constant),
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Var(Cell<VarReg>, Rc<Var>)
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}
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pub enum InlinedQueryTerm {
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CompareNumber(CompareNumberQT, Vec<Box<Term>>),
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IsAtomic(Vec<Box<Term>>),
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IsCompound(Vec<Box<Term>>),
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IsInteger(Vec<Box<Term>>),
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IsRational(Vec<Box<Term>>),
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IsString(Vec<Box<Term>>),
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IsFloat(Vec<Box<Term>>),
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IsNonVar(Vec<Box<Term>>),
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IsVar(Vec<Box<Term>>),
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}
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impl InlinedQueryTerm {
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pub fn arity(&self) -> usize {
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match self {
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&InlinedQueryTerm::CompareNumber(_, _) => 2,
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&InlinedQueryTerm::IsAtomic(_) => 1,
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&InlinedQueryTerm::IsCompound(_) => 1,
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&InlinedQueryTerm::IsFloat(_) => 1,
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&InlinedQueryTerm::IsRational(_) => 1,
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&InlinedQueryTerm::IsString(_) => 1,
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&InlinedQueryTerm::IsNonVar(_) => 1,
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&InlinedQueryTerm::IsInteger(_) => 1,
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&InlinedQueryTerm::IsVar(_) => 1,
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}
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}
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}
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#[derive(Clone, Copy)]
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pub enum CompareNumberQT {
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GreaterThan,
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LessThan,
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GreaterThanOrEqual,
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LessThanOrEqual,
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NotEqual,
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Equal
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}
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impl CompareNumberQT {
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fn name<'a>(self) -> &'a str {
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match self {
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CompareNumberQT::GreaterThan => ">",
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CompareNumberQT::LessThan => "<",
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CompareNumberQT::GreaterThanOrEqual => ">=",
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CompareNumberQT::LessThanOrEqual => "=<",
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CompareNumberQT::NotEqual => "=\\=",
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CompareNumberQT::Equal => "=:="
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}
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}
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}
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#[derive(Clone, Copy)]
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pub enum CompareTermQT {
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LessThan,
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LessThanOrEqual,
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Equal,
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GreaterThanOrEqual,
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GreaterThan,
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NotEqual,
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}
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impl CompareTermQT {
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fn name<'a>(self) -> &'a str {
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match self {
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CompareTermQT::GreaterThan => "@>",
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CompareTermQT::LessThan => "@<",
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CompareTermQT::GreaterThanOrEqual => "@>=",
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CompareTermQT::LessThanOrEqual => "@=<",
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CompareTermQT::NotEqual => "\\=@=",
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CompareTermQT::Equal => "=@="
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}
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}
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}
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// vars of predicate, toplevel offset. Vec<Term> is always a vector
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// of vars (we get their adjoining cells this way).
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pub type JumpStub = Vec<Term>;
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pub enum QueryTerm {
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Arg(Vec<Box<Term>>),
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CallN(Vec<Box<Term>>),
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CallWithInferenceLimit(Vec<Box<Term>>),
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Catch(Vec<Box<Term>>),
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Compare(Vec<Box<Term>>),
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CompareTerm(CompareTermQT, Vec<Box<Term>>),
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Cut,
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Display(Vec<Box<Term>>),
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DuplicateTerm(Vec<Box<Term>>),
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Eq(Vec<Box<Term>>),
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Functor(Vec<Box<Term>>),
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Ground(Vec<Box<Term>>),
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Inlined(InlinedQueryTerm),
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Is(Vec<Box<Term>>),
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Jump(JumpStub),
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NotEq(Vec<Box<Term>>),
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SetupCallCleanup(Vec<Box<Term>>),
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Term(Term),
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Throw(Vec<Box<Term>>)
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}
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impl QueryTerm {
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pub fn arity(&self) -> usize {
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match self {
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&QueryTerm::Arg(_) => 3,
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&QueryTerm::Catch(_) => 3,
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&QueryTerm::Compare(_) => 3,
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&QueryTerm::CompareTerm(..) => 2,
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&QueryTerm::Display(_) => 1,
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&QueryTerm::Throw(_) => 1,
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&QueryTerm::DuplicateTerm(_) => 2,
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&QueryTerm::Eq(_) => 2,
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&QueryTerm::Functor(_) => 3,
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&QueryTerm::Ground(_) => 1,
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&QueryTerm::Inlined(ref term) => term.arity(),
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&QueryTerm::Is(_) => 2,
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&QueryTerm::Jump(ref vars) => vars.len(),
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&QueryTerm::NotEq(_) => 2,
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&QueryTerm::CallN(ref terms) => terms.len(),
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&QueryTerm::CallWithInferenceLimit(_) => 3,
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&QueryTerm::Cut => 0,
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&QueryTerm::SetupCallCleanup(_) => 3,
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&QueryTerm::Term(ref term) => term.arity(),
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}
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}
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}
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pub struct Rule {
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pub head: (QueryTerm, QueryTerm),
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pub clauses: Vec<QueryTerm>
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}
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|
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#[derive(Clone, Copy)]
|
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pub enum ClauseType<'a> {
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Arg,
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CallN,
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CallWithInferenceLimit,
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Catch,
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Compare,
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CompareNumber(CompareNumberQT),
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CompareTerm(CompareTermQT),
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Deep(Level, &'a Cell<RegType>, &'a TabledRc<Atom>, Option<Fixity>),
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|
Display,
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|
DuplicateTerm,
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|
Eq,
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|
Functor,
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|
Ground,
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|
Is,
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NotEq,
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Root(&'a TabledRc<Atom>),
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SetupCallCleanup,
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Throw,
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}
|
|
|
|
impl<'a> ClauseType<'a> {
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pub fn name(&self) -> &'a str {
|
|
match self {
|
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&ClauseType::Arg => "arg",
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&ClauseType::CallN => "call",
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&ClauseType::CallWithInferenceLimit => "call_with_inference_limit",
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&ClauseType::Catch => "catch",
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&ClauseType::Compare => "compare",
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&ClauseType::CompareNumber(qt) => qt.name(),
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&ClauseType::CompareTerm(qt) => qt.name(),
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&ClauseType::Display => "display",
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&ClauseType::Deep(_, _, name, _) => name.as_str(),
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|
&ClauseType::DuplicateTerm => "duplicate_term",
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&ClauseType::Eq => "==",
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|
&ClauseType::Functor => "functor",
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|
&ClauseType::Ground => "ground",
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&ClauseType::Is => "is",
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&ClauseType::NotEq => "\\==",
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&ClauseType::Root(name) => name.as_str(),
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&ClauseType::SetupCallCleanup => "setup_call_cleanup",
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&ClauseType::Throw => "throw"
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}
|
|
}
|
|
|
|
pub fn level_of_subterms(self) -> Level {
|
|
match self {
|
|
ClauseType::Deep(..) => Level::Deep,
|
|
_ => Level::Shallow
|
|
}
|
|
}
|
|
}
|
|
|
|
#[derive(Clone, Copy)]
|
|
pub enum TermRef<'a> {
|
|
AnonVar(Level),
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|
Cons(Level, &'a Cell<RegType>, &'a Term, &'a Term),
|
|
Constant(Level, &'a Cell<RegType>, &'a Constant),
|
|
Clause(ClauseType<'a>, &'a Vec<Box<Term>>),
|
|
Var(Level, &'a Cell<VarReg>, &'a Var)
|
|
}
|
|
|
|
impl<'a> TermRef<'a> {
|
|
pub fn level(self) -> Level {
|
|
match self {
|
|
TermRef::AnonVar(lvl)
|
|
| TermRef::Cons(lvl, ..)
|
|
| TermRef::Constant(lvl, ..)
|
|
| TermRef::Var(lvl, ..) => lvl,
|
|
TermRef::Clause(ClauseType::Deep(lvl, ..), ..) => lvl,
|
|
_ => Level::Shallow
|
|
}
|
|
}
|
|
}
|
|
|
|
pub enum ChoiceInstruction {
|
|
RetryMeElse(usize),
|
|
TrustMe,
|
|
TryMeElse(usize)
|
|
}
|
|
|
|
pub enum CutInstruction {
|
|
Cut(RegType),
|
|
GetLevel(RegType),
|
|
NeckCut
|
|
}
|
|
|
|
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
|
|
}
|
|
}
|
|
}
|
|
|
|
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)
|
|
}
|
|
|
|
pub enum BuiltInInstruction {
|
|
CleanUpBlock,
|
|
CompareNumber(CompareNumberQT, ArithmeticTerm, ArithmeticTerm),
|
|
DefaultTrustMe,
|
|
DynamicCompareNumber(CompareNumberQT),
|
|
EraseBall,
|
|
Fail,
|
|
GetArgCall,
|
|
GetArgExecute,
|
|
GetBall,
|
|
GetCurrentBlock,
|
|
GetCutPoint(RegType),
|
|
InferenceLevel(RegType, RegType),
|
|
InstallCleaner,
|
|
InstallInferenceCounter(RegType, RegType, RegType),
|
|
InstallNewBlock,
|
|
InternalCallN,
|
|
IsAtomic(RegType),
|
|
IsCompound(RegType),
|
|
IsFloat(RegType),
|
|
IsInteger(RegType),
|
|
IsNonVar(RegType),
|
|
IsRational(RegType),
|
|
IsString(RegType),
|
|
IsVar(RegType),
|
|
RemoveCallPolicyCheck,
|
|
RemoveInferenceCounter(RegType, RegType),
|
|
ResetBlock,
|
|
RestoreCutPolicy,
|
|
SetBall,
|
|
SetCutPoint(RegType),
|
|
Succeed,
|
|
Unify,
|
|
UnwindStack
|
|
}
|
|
|
|
#[derive(Clone)]
|
|
pub enum ControlInstruction {
|
|
Allocate(usize), // num_frames.
|
|
ArgCall,
|
|
ArgExecute,
|
|
Call(TabledRc<Atom>, usize, usize), // name, arity, perm_vars after threshold.
|
|
CallN(usize), // arity.
|
|
CatchCall,
|
|
CatchExecute,
|
|
CheckCpExecute,
|
|
CompareCall,
|
|
CompareExecute,
|
|
CompareTermCall(CompareTermQT),
|
|
CompareTermExecute(CompareTermQT),
|
|
DisplayCall,
|
|
DisplayExecute,
|
|
Deallocate,
|
|
DuplicateTermCall,
|
|
DuplicateTermExecute,
|
|
DynamicIs,
|
|
EqCall,
|
|
EqExecute,
|
|
Execute(TabledRc<Atom>, usize),
|
|
ExecuteN(usize),
|
|
FunctorCall,
|
|
FunctorExecute,
|
|
GetCleanerCall,
|
|
GotoCall(usize, usize), // p, arity.
|
|
GotoExecute(usize, usize), // p, arity.
|
|
GroundCall,
|
|
GroundExecute,
|
|
JmpByCall(usize, usize), // arity, global_offset.
|
|
JmpByExecute(usize, usize),
|
|
IsCall(RegType, ArithmeticTerm),
|
|
IsExecute(RegType, ArithmeticTerm),
|
|
NotEqCall,
|
|
NotEqExecute,
|
|
Proceed,
|
|
ThrowCall,
|
|
ThrowExecute,
|
|
}
|
|
|
|
impl ControlInstruction {
|
|
pub fn is_jump_instr(&self) -> bool {
|
|
match self {
|
|
&ControlInstruction::ArgCall => true,
|
|
&ControlInstruction::ArgExecute => true,
|
|
&ControlInstruction::Call(_, _, _) => true,
|
|
&ControlInstruction::CatchCall => true,
|
|
&ControlInstruction::CatchExecute => true,
|
|
&ControlInstruction::CompareTermCall(..) => true,
|
|
&ControlInstruction::CompareTermExecute(..) => true,
|
|
&ControlInstruction::DisplayCall => true,
|
|
&ControlInstruction::DisplayExecute => true,
|
|
&ControlInstruction::DuplicateTermCall => true,
|
|
&ControlInstruction::DuplicateTermExecute => true,
|
|
&ControlInstruction::DynamicIs => true,
|
|
&ControlInstruction::EqCall => true,
|
|
&ControlInstruction::EqExecute => true,
|
|
&ControlInstruction::Execute(_, _) => true,
|
|
&ControlInstruction::CallN(_) => true,
|
|
&ControlInstruction::ExecuteN(_) => true,
|
|
&ControlInstruction::FunctorCall => true,
|
|
&ControlInstruction::FunctorExecute => true,
|
|
&ControlInstruction::NotEqCall => true,
|
|
&ControlInstruction::NotEqExecute => true,
|
|
&ControlInstruction::ThrowCall => true,
|
|
&ControlInstruction::ThrowExecute => true,
|
|
&ControlInstruction::GetCleanerCall => true,
|
|
&ControlInstruction::GotoCall(..) => true,
|
|
&ControlInstruction::GotoExecute(..) => true,
|
|
&ControlInstruction::GroundCall => true,
|
|
&ControlInstruction::GroundExecute => true,
|
|
&ControlInstruction::IsCall(..) => true,
|
|
&ControlInstruction::IsExecute(..) => true,
|
|
&ControlInstruction::JmpByCall(..) => true,
|
|
&ControlInstruction::JmpByExecute(..) => true,
|
|
&ControlInstruction::CompareCall => true,
|
|
&ControlInstruction::CompareExecute => true,
|
|
_ => false
|
|
}
|
|
}
|
|
}
|
|
|
|
pub enum IndexingInstruction {
|
|
SwitchOnTerm(usize, usize, usize, usize),
|
|
SwitchOnConstant(usize, HashMap<Constant, usize>),
|
|
SwitchOnStructure(usize, HashMap<(TabledRc<Atom>, usize), usize>)
|
|
}
|
|
|
|
impl From<IndexingInstruction> for Line {
|
|
fn from(i: IndexingInstruction) -> Self {
|
|
Line::Indexing(i)
|
|
}
|
|
}
|
|
|
|
pub enum FactInstruction {
|
|
GetConstant(Level, Constant, RegType),
|
|
GetList(Level, RegType),
|
|
GetStructure(Level, TabledRc<Atom>, usize, RegType, Option<Fixity>),
|
|
GetValue(RegType, usize),
|
|
GetVariable(RegType, usize),
|
|
UnifyConstant(Constant),
|
|
UnifyLocalValue(RegType),
|
|
UnifyVariable(RegType),
|
|
UnifyValue(RegType),
|
|
UnifyVoid(usize)
|
|
}
|
|
|
|
pub enum QueryInstruction {
|
|
GetVariable(RegType, usize),
|
|
PutConstant(Level, Constant, RegType),
|
|
PutList(Level, RegType),
|
|
PutStructure(Level, TabledRc<Atom>, usize, RegType, Option<Fixity>),
|
|
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>;
|
|
|
|
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 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, PartialEq)]
|
|
pub enum Ref {
|
|
HeapCell(usize),
|
|
StackCell(usize, usize)
|
|
}
|
|
|
|
#[derive(Clone, PartialEq)]
|
|
pub enum HeapCellValue {
|
|
Addr(Addr),
|
|
NamedStr(usize, TabledRc<Atom>, 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 CodePtr {
|
|
DirEntry(usize),
|
|
TopLevel(usize, usize) // chunk_num, offset.
|
|
}
|
|
|
|
impl PartialOrd<CodePtr> for CodePtr {
|
|
fn partial_cmp(&self, other: &CodePtr) -> Option<Ordering> {
|
|
match (self, other) {
|
|
(&CodePtr::DirEntry(p1), &CodePtr::DirEntry(ref p2)) =>
|
|
p1.partial_cmp(p2),
|
|
(&CodePtr::DirEntry(_), &CodePtr::TopLevel(_, _)) =>
|
|
Some(Ordering::Less),
|
|
(&CodePtr::TopLevel(_, p1), &CodePtr::TopLevel(_, ref p2)) =>
|
|
p1.partial_cmp(p2),
|
|
_ => Some(Ordering::Greater)
|
|
}
|
|
}
|
|
}
|
|
|
|
impl Default for CodePtr {
|
|
fn default() -> Self {
|
|
CodePtr::TopLevel(0, 0)
|
|
}
|
|
}
|
|
|
|
impl Add<usize> for CodePtr {
|
|
type Output = CodePtr;
|
|
|
|
fn add(self, rhs: usize) -> Self::Output {
|
|
match self {
|
|
CodePtr::DirEntry(p) => CodePtr::DirEntry(p + rhs),
|
|
CodePtr::TopLevel(cn, p) => CodePtr::TopLevel(cn, p + rhs)
|
|
}
|
|
}
|
|
}
|
|
|
|
impl AddAssign<usize> for CodePtr {
|
|
fn add_assign(&mut self, rhs: usize) {
|
|
match self {
|
|
&mut CodePtr::DirEntry(ref mut p) |
|
|
&mut CodePtr::TopLevel(_, ref mut p) => *p += 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 first_arg(&self) -> Option<&Term> {
|
|
match self {
|
|
&Term::Clause(_, _, ref terms, _) =>
|
|
terms.first().map(|bt| bt.as_ref()),
|
|
_ => None
|
|
}
|
|
}
|
|
|
|
pub fn is_callable(&self) -> bool {
|
|
match self {
|
|
&Term::Clause(..) | &Term::Constant(_, Constant::Atom(_)) =>
|
|
true,
|
|
_ => false
|
|
}
|
|
}
|
|
|
|
pub fn name(&self) -> Option<TabledRc<Atom>> {
|
|
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),
|
|
Clause(usize, ClauseType<'a>, &'a Vec<Box<Term>>),
|
|
Constant(Level, &'a Cell<RegType>, &'a Constant),
|
|
InitialCons(Level, &'a Cell<RegType>, &'a Term, &'a Term),
|
|
FinalCons(Level, &'a Cell<RegType>, &'a Term, &'a Term),
|
|
Var(Level, &'a Cell<VarReg>, &'a Var)
|
|
}
|
|
|
|
impl<'a> TermIterState<'a> {
|
|
pub fn to_state(lvl: Level, term: &'a Term) -> TermIterState<'a> {
|
|
match term {
|
|
&Term::AnonVar =>
|
|
TermIterState::AnonVar(lvl),
|
|
&Term::Clause(ref cell, ref atom, ref child_terms, fixity) =>
|
|
TermIterState::Clause(0, ClauseType::Deep(lvl, cell, atom, fixity), child_terms),
|
|
&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)
|
|
}
|
|
}
|
|
}
|