refactor to actual modules
This commit is contained in:
Mark Thom
887
src/prolog/machine/toplevel.rs
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887
src/prolog/machine/toplevel.rs
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@@ -0,0 +1,887 @@
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use prolog_parser::ast::*;
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use prolog_parser::tabled_rc::*;
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use prolog::forms::*;
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use prolog::iterators::*;
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use prolog::machine::*;
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use prolog::machine::code_repo::*;
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use prolog::machine::machine_errors::*;
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use prolog::machine::machine_indices::*;
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use prolog::machine::machine_state::MachineState;
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use prolog::machine::term_expansion::*;
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use prolog::num::*;
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use std::borrow::BorrowMut;
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use std::collections::{HashMap, HashSet, VecDeque};
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use std::cell::Cell;
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use std::io::Read;
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use std::mem;
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use std::rc::Rc;
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struct CompositeIndices<'a, 'b> {
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local: &'a mut IndexStore,
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static_code_dir: Option<&'b CodeDir>
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}
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macro_rules! composite_indices {
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($in_module: expr, $local: expr, $static_code_dir: expr) => (
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CompositeIndices { local: $local,
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static_code_dir: if $in_module {
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None
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} else {
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Some($static_code_dir)
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}}
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);
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($local: expr) => (
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CompositeIndices { local: $local, static_code_dir: None }
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)
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}
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impl<'a, 'b> CompositeIndices<'a, 'b>
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{
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fn get_code_index(&mut self, name: ClauseName, arity: usize) -> CodeIndex {
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let idx_opt = self.local.code_dir.get(&(name.clone(), arity))
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.or_else(|| {
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match &self.static_code_dir {
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&Some(ref code_dir) => code_dir.get(&(name.clone(), arity)),
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_ => None
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}
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}).cloned();
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if let Some(idx) = idx_opt {
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self.local.code_dir.insert((name, arity), idx.clone());
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idx
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} else {
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let idx = CodeIndex::default();
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self.local.code_dir.insert((name, arity), idx.clone());
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idx
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}
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}
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fn get_clause_type(&mut self, name: ClauseName, arity: usize, spec: Option<(usize, Specifier)>) -> ClauseType
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{
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match ClauseType::from(name, arity, spec) {
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ClauseType::Named(name, arity, _) => {
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let idx = self.get_code_index(name.clone(), arity);
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ClauseType::Named(name, arity, idx.clone())
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},
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ClauseType::Op(op_decl, _) => {
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let idx = self.get_code_index(op_decl.2.clone(), arity);
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ClauseType::Op(op_decl, idx.clone())
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},
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ct => ct
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}
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}
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}
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fn as_compile_time_hook(name: &str, arity: usize, terms: &Vec<Box<Term>>) -> Option<CompileTimeHook>
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{
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match (name, arity) {
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("term_expansion", 2) => Some(CompileTimeHook::TermExpansion),
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("goal_expansion", 2) => Some(CompileTimeHook::GoalExpansion),
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(":", 2) => {
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if let &Term::Constant(_, Constant::Atom(ref name, _)) = &terms[0].as_ref() {
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if name.as_str() == "user" {
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if let &Term::Clause(_, ref name, ref terms, _) = &terms[1].as_ref() {
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return match name.as_str() {
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"term_expansion" if terms.len() == 2 =>
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Some(CompileTimeHook::UserTermExpansion),
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"goal_expansion" if terms.len() == 2 =>
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Some(CompileTimeHook::UserGoalExpansion),
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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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None
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},
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_ => None
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}
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}
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#[inline]
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fn is_compile_time_hook(name: &ClauseName, terms: &Vec<Box<Term>>) -> Option<CompileTimeHook> {
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if name.as_str() == ":-" {
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if let Some(ref term) = terms.first() {
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if let &Term::Clause(_, ref name, ref terms, _) = term.as_ref() {
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return as_compile_time_hook(name.as_str(), terms.len(), terms);
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}
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}
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}
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as_compile_time_hook(name.as_str(), terms.len(), terms)
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}
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type CompileTimeHookCompileInfo = (CompileTimeHook, PredicateClause, VecDeque<TopLevel>);
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fn setup_op_decl(mut terms: Vec<Box<Term>>) -> Result<OpDecl, ParserError>
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{
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let name = match *terms.pop().unwrap() {
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Term::Constant(_, Constant::Atom(name, _)) => name,
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_ => return Err(ParserError::InconsistentEntry)
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};
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let spec = match *terms.pop().unwrap() {
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Term::Constant(_, Constant::Atom(name, _)) => name,
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_ => return Err(ParserError::InconsistentEntry)
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};
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let prec = match *terms.pop().unwrap() {
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Term::Constant(_, Constant::Number(Number::Integer(bi))) =>
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match bi.to_usize() {
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Some(n) if n <= 1200 => n,
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_ => return Err(ParserError::InconsistentEntry)
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},
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_ => return Err(ParserError::InconsistentEntry)
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};
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match spec.as_str() {
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"xfx" => Ok(OpDecl(prec, XFX, name)),
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"xfy" => Ok(OpDecl(prec, XFY, name)),
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"yfx" => Ok(OpDecl(prec, YFX, name)),
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"fx" => Ok(OpDecl(prec, FX, name)),
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"fy" => Ok(OpDecl(prec, FY, name)),
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"xf" => Ok(OpDecl(prec, XF, name)),
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"yf" => Ok(OpDecl(prec, YF, name)),
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_ => Err(ParserError::InconsistentEntry)
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}
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}
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fn setup_predicate_indicator(mut term: Term) -> Result<PredicateKey, ParserError>
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{
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match term {
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Term::Clause(_, ref name, ref mut terms, Some(_))
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if name.as_str() == "/" && terms.len() == 2 => {
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let arity = *terms.pop().unwrap();
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let name = *terms.pop().unwrap();
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let arity = arity.to_constant().and_then(|c| c.to_integer())
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.and_then(|n| if !n.is_negative() { n.to_usize() } else { None })
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.ok_or(ParserError::InvalidModuleExport)?;
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let name = name.to_constant().and_then(|c| c.to_atom())
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.ok_or(ParserError::InvalidModuleExport)?;
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Ok((name, arity))
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},
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_ => Err(ParserError::InvalidModuleExport)
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}
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}
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fn setup_module_decl(mut terms: Vec<Box<Term>>) -> Result<ModuleDecl, ParserError>
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{
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let mut export_list = *terms.pop().unwrap();
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let name = terms.pop().unwrap().to_constant().and_then(|c| c.to_atom())
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.ok_or(ParserError::InvalidModuleDecl)?;
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let mut exports = Vec::new();
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while let Term::Cons(_, t1, t2) = export_list {
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exports.push(setup_predicate_indicator(*t1)?);
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export_list = *t2;
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}
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if export_list.to_constant() != Some(Constant::EmptyList) {
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Err(ParserError::InvalidModuleDecl)
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} else {
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Ok(ModuleDecl { name, exports })
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}
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}
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fn setup_use_module_decl(mut terms: Vec<Box<Term>>) -> Result<ClauseName, ParserError>
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{
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match *terms.pop().unwrap() {
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Term::Clause(_, ref name, ref mut terms, None)
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if name.as_str() == "library" && terms.len() == 1 => {
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terms.pop().unwrap().to_constant()
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.and_then(|c| c.to_atom())
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.ok_or(ParserError::InvalidUseModuleDecl)
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},
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_ => Err(ParserError::InvalidUseModuleDecl)
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}
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}
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type UseModuleExport = (ClauseName, Vec<PredicateKey>);
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fn setup_qualified_import(mut terms: Vec<Box<Term>>) -> Result<UseModuleExport, ParserError>
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{
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let mut export_list = *terms.pop().unwrap();
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let name = match *terms.pop().unwrap() {
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Term::Clause(_, ref name, ref mut terms, None)
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if name.as_str() == "library" && terms.len() == 1 => {
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terms.pop().unwrap().to_constant()
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.and_then(|c| c.to_atom())
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.ok_or(ParserError::InvalidUseModuleDecl)
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},
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_ => Err(ParserError::InvalidUseModuleDecl)
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}?;
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let mut exports = Vec::new();
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while let Term::Cons(_, t1, t2) = export_list {
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exports.push(setup_predicate_indicator(*t1)?);
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export_list = *t2;
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}
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if export_list.to_constant() != Some(Constant::EmptyList) {
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Err(ParserError::InvalidModuleDecl)
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} else {
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Ok((name, exports))
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}
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}
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fn setup_declaration(term: Term) -> Result<Declaration, ParserError>
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{
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match term {
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Term::Clause(_, name, mut terms, _) =>
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if name.as_str() == "op" && terms.len() == 3 {
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Ok(Declaration::Op(setup_op_decl(terms)?))
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} else if name.as_str() == "module" && terms.len() == 2 {
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Ok(Declaration::Module(setup_module_decl(terms)?))
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} else if name.as_str() == "use_module" && terms.len() == 1 {
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Ok(Declaration::UseModule(setup_use_module_decl(terms)?))
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} else if name.as_str() == "use_module" && terms.len() == 2 {
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let (name, exports) = setup_qualified_import(terms)?;
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Ok(Declaration::UseQualifiedModule(name, exports))
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} else if name.as_str() == "non_counted_backtracking" && terms.len() == 1 {
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let (name, arity) = setup_predicate_indicator(*terms.pop().unwrap())?;
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Ok(Declaration::NonCountedBacktracking(name, arity))
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} else if name.as_str() == "dynamic" && terms.len() == 1 {
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let (name, arity) = setup_predicate_indicator(*terms.pop().unwrap())?;
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Ok(Declaration::Dynamic(name, arity))
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} else {
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Err(ParserError::InconsistentEntry)
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},
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_ => return Err(ParserError::InconsistentEntry)
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}
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}
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fn is_consistent(tl: &TopLevel, clauses: &Vec<PredicateClause>) -> bool
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{
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match clauses.first() {
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Some(ref cl) => tl.name() == cl.name() && tl.arity() == cl.arity(),
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None => true
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}
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}
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fn deque_to_packet(head: TopLevel, deque: VecDeque<TopLevel>) -> TopLevelPacket
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{
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match head {
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TopLevel::Query(query) => TopLevelPacket::Query(query, deque),
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tl => TopLevelPacket::Decl(tl, deque)
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}
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}
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fn merge_clauses(tls: &mut VecDeque<TopLevel>) -> Result<TopLevel, ParserError>
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{
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let mut clauses: Vec<PredicateClause> = vec![];
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while let Some(tl) = tls.pop_front() {
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match tl {
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TopLevel::Query(_) if clauses.is_empty() && tls.is_empty() =>
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return Ok(tl),
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TopLevel::Declaration(_) if clauses.is_empty() =>
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return Ok(tl),
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TopLevel::Query(_) =>
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return Err(ParserError::InconsistentEntry),
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TopLevel::Fact(_) if is_consistent(&tl, &clauses) =>
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if let TopLevel::Fact(fact) = tl {
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let clause = PredicateClause::Fact(fact);
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clauses.push(clause);
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},
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TopLevel::Rule(_) if is_consistent(&tl, &clauses) =>
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if let TopLevel::Rule(rule) = tl {
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let clause = PredicateClause::Rule(rule);
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clauses.push(clause);
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},
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TopLevel::Predicate(_) if is_consistent(&tl, &clauses) =>
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if let TopLevel::Predicate(pred) = tl {
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clauses.extend(pred.clauses().into_iter())
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},
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_ => {
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tls.push_front(tl);
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break;
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}
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}
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}
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if clauses.is_empty() {
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Err(ParserError::InconsistentEntry)
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} else {
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Ok(TopLevel::Predicate(Predicate(clauses)))
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}
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}
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fn append_preds(preds: &mut Vec<PredicateClause>) -> Predicate {
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Predicate(mem::replace(preds, vec![]))
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}
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fn mark_cut_variables_as(terms: &mut Vec<Term>, name: ClauseName) {
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for term in terms.iter_mut() {
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match term {
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&mut Term::Constant(_, Constant::Atom(ref mut var, _)) if var.as_str() == "!" =>
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*var = name.clone(),
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_ => {}
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}
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}
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}
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fn mark_cut_variable(term: &mut Term) -> bool {
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let cut_var_found = match term {
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&mut Term::Constant(_, Constant::Atom(ref var, _)) if var.as_str() == "!" => true,
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_ => false
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};
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if cut_var_found {
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*term = Term::Var(Cell::default(), rc_atom!("!"));
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true
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} else {
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false
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}
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}
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fn mark_cut_variables(terms: &mut Vec<Term>) -> bool {
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let mut found_cut_var = false;
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for item in terms.iter_mut() {
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found_cut_var = mark_cut_variable(item) || found_cut_var;
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}
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found_cut_var
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}
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fn flatten_hook(mut term: Term) -> Term {
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if let &mut Term::Clause(_, ref mut name, ref mut terms, _) = &mut term {
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match (name.as_str(), terms.len()) {
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(":-", 2) => {
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let inner_term = match terms.first_mut().map(|term| term.borrow_mut()) {
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Some(&mut Term::Clause(_, ref name, ref mut inner_terms, _)) =>
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if name.as_str() == ":" && inner_terms.len() == 2 {
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Some(*inner_terms.pop().unwrap())
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} else {
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None
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},
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_ => None
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};
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if let Some(mut inner_term) = inner_term {
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mem::swap(&mut terms[0], &mut Box::new(inner_term));
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}
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},
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(":", 2) => return *terms.pop().unwrap(),
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_ => {}
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}
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}
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term
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}
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pub enum TopLevelPacket {
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Query(Vec<QueryTerm>, VecDeque<TopLevel>),
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Decl(TopLevel, VecDeque<TopLevel>)
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}
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struct RelationWorker {
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dynamic_clauses: Vec<(Term, Term)>, // Head, Body.
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queue: VecDeque<VecDeque<Term>>,
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}
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impl RelationWorker {
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fn new() -> Self {
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RelationWorker { dynamic_clauses: vec![],
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queue: VecDeque::new() }
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}
|
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|
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fn setup_fact(&mut self, term: Term) -> Result<Term, ParserError>
|
||||
{
|
||||
match term {
|
||||
Term::Clause(..) | Term::Constant(_, Constant::Atom(..)) => {
|
||||
let tail = Term::Constant(Cell::default(),
|
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Constant::Atom(clause_name!("true"), None));
|
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|
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self.dynamic_clauses.push((term.clone(), tail));
|
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Ok(term)
|
||||
},
|
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_ =>
|
||||
Err(ParserError::InadmissibleFact)
|
||||
}
|
||||
}
|
||||
|
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fn compute_head(&self, term: &Term) -> Vec<Term>
|
||||
{
|
||||
let mut vars = HashSet::new();
|
||||
|
||||
for term in post_order_iter(term) {
|
||||
if let TermRef::Var(_, _, v) = term {
|
||||
vars.insert(v.clone());
|
||||
}
|
||||
}
|
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|
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vars.insert(rc_atom!("!"));
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vars.into_iter()
|
||||
.map(|v| Term::Var(Cell::default(), v))
|
||||
.collect()
|
||||
}
|
||||
|
||||
fn fabricate_rule_body(&self, vars: &Vec<Term>, body_term: Term) -> Term
|
||||
{
|
||||
let vars_of_head = vars.iter().cloned().map(Box::new).collect();
|
||||
let head_term = Term::Clause(Cell::default(), clause_name!(""), vars_of_head, None);
|
||||
|
||||
let rule = vec![Box::new(head_term), Box::new(body_term)];
|
||||
let turnstile = clause_name!(":-");
|
||||
|
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Term::Clause(Cell::default(), turnstile, rule, None)
|
||||
}
|
||||
|
||||
// the terms form the body of the rule. We create a head, by
|
||||
// gathering variables from the body of terms and recording them
|
||||
// in the head clause.
|
||||
fn fabricate_rule(&self, body_term: Term) -> (JumpStub, VecDeque<Term>)
|
||||
{
|
||||
// collect the vars of body_term into a head, return the num_vars
|
||||
// (the arity) as well.
|
||||
let vars = self.compute_head(&body_term);
|
||||
let rule = self.fabricate_rule_body(&vars, body_term);
|
||||
|
||||
(vars, VecDeque::from(vec![rule]))
|
||||
}
|
||||
|
||||
fn fabricate_disjunct(&self, body_term: Term) -> (JumpStub, VecDeque<Term>)
|
||||
{
|
||||
let vars = self.compute_head(&body_term);
|
||||
let clauses: Vec<_> = unfold_by_str(body_term, ";").into_iter()
|
||||
.map(|term| {
|
||||
let mut subterms = unfold_by_str(term, ",");
|
||||
mark_cut_variables(&mut subterms);
|
||||
|
||||
let term = subterms.pop().unwrap();
|
||||
fold_by_str(subterms.into_iter(), term, clause_name!(","))
|
||||
}).collect();
|
||||
|
||||
let results = clauses.into_iter()
|
||||
.map(|clause| self.fabricate_rule_body(&vars, clause))
|
||||
.collect();
|
||||
|
||||
(vars, results)
|
||||
}
|
||||
|
||||
fn fabricate_if_then(&self, prec: Term, conq: Term) -> (JumpStub, VecDeque<Term>)
|
||||
{
|
||||
let mut prec_seq = unfold_by_str(prec, ",");
|
||||
let comma_sym = clause_name!(",");
|
||||
let cut_sym = atom!("!");
|
||||
|
||||
prec_seq.push(Term::Constant(Cell::default(), cut_sym));
|
||||
|
||||
mark_cut_variables_as(&mut prec_seq, clause_name!("blocked_!"));
|
||||
|
||||
let mut conq_seq = unfold_by_str(conq, ",");
|
||||
|
||||
mark_cut_variables(&mut conq_seq);
|
||||
prec_seq.extend(conq_seq.into_iter());
|
||||
|
||||
let back_term = Box::new(prec_seq.pop().unwrap());
|
||||
let front_term = Box::new(prec_seq.pop().unwrap());
|
||||
|
||||
let body_term = Term::Clause(Cell::default(), comma_sym.clone(),
|
||||
vec![front_term, back_term], None);
|
||||
|
||||
self.fabricate_rule(fold_by_str(prec_seq.into_iter(), body_term, comma_sym))
|
||||
}
|
||||
|
||||
fn to_query_term(&mut self, indices: &mut CompositeIndices, term: Term) -> Result<QueryTerm, ParserError>
|
||||
{
|
||||
match term {
|
||||
Term::Constant(_, Constant::Atom(name, fixity)) =>
|
||||
if name.as_str() == "!" || name.as_str() == "blocked_!" {
|
||||
Ok(QueryTerm::BlockedCut)
|
||||
} else {
|
||||
let ct = indices.get_clause_type(name, 0, fixity);
|
||||
Ok(QueryTerm::Clause(Cell::default(), ct, vec![], false))
|
||||
},
|
||||
Term::Var(_, ref v) if v.as_str() == "!" =>
|
||||
Ok(QueryTerm::UnblockedCut(Cell::default())),
|
||||
Term::Clause(r, name, mut terms, fixity) =>
|
||||
match (name.as_str(), terms.len()) {
|
||||
(";", 2) => {
|
||||
let term = Term::Clause(r, name.clone(), terms, fixity);
|
||||
let (stub, clauses) = self.fabricate_disjunct(term);
|
||||
|
||||
self.queue.push_back(clauses);
|
||||
Ok(QueryTerm::Jump(stub))
|
||||
},
|
||||
("->", 2) => {
|
||||
let conq = *terms.pop().unwrap();
|
||||
let prec = *terms.pop().unwrap();
|
||||
|
||||
let (stub, clauses) = self.fabricate_if_then(prec, conq);
|
||||
|
||||
self.queue.push_back(clauses);
|
||||
Ok(QueryTerm::Jump(stub))
|
||||
},
|
||||
("$get_level", 1) =>
|
||||
if let Term::Var(_, ref var) = *terms[0] {
|
||||
Ok(QueryTerm::GetLevelAndUnify(Cell::default(), var.clone()))
|
||||
} else {
|
||||
Err(ParserError::InadmissibleQueryTerm)
|
||||
},
|
||||
("partial_string", 2) => {
|
||||
if let Term::Constant(_, Constant::String(_)) = *terms[0].clone() {
|
||||
if let Term::Var(..) = *terms[1].clone() {
|
||||
let ct = ClauseType::BuiltIn(BuiltInClauseType::PartialString);
|
||||
return Ok(QueryTerm::Clause(Cell::default(), ct, terms, false));
|
||||
}
|
||||
}
|
||||
|
||||
Err(ParserError::InadmissibleQueryTerm)
|
||||
},
|
||||
_ => {
|
||||
let ct = indices.get_clause_type(name, terms.len(), fixity);
|
||||
Ok(QueryTerm::Clause(Cell::default(), ct, terms, false))
|
||||
}
|
||||
},
|
||||
Term::Var(..) =>
|
||||
Ok(QueryTerm::Clause(Cell::default(), ClauseType::CallN, vec![Box::new(term)], false)),
|
||||
_ => Err(ParserError::InadmissibleQueryTerm)
|
||||
}
|
||||
}
|
||||
|
||||
// never blocks cuts in the consequent.
|
||||
fn prepend_if_then(&self, prec: Term, conq: Term, queue: &mut VecDeque<Box<Term>>,
|
||||
blocks_cuts: bool)
|
||||
{
|
||||
let cut_symb = atom!("blocked_!");
|
||||
let mut terms_seq = unfold_by_str(prec, ",");
|
||||
|
||||
terms_seq.push(Term::Constant(Cell::default(), cut_symb));
|
||||
|
||||
let mut conq_seq = unfold_by_str(conq, ",");
|
||||
|
||||
if !blocks_cuts {
|
||||
for item in conq_seq.iter_mut() {
|
||||
mark_cut_variable(item);
|
||||
}
|
||||
}
|
||||
|
||||
terms_seq.append(&mut conq_seq);
|
||||
|
||||
while let Some(term) = terms_seq.pop() {
|
||||
queue.push_front(Box::new(term));
|
||||
}
|
||||
}
|
||||
|
||||
fn pre_query_term(&mut self, indices: &mut CompositeIndices, term: Term) -> Result<QueryTerm, ParserError>
|
||||
{
|
||||
match term {
|
||||
Term::Clause(r, name, mut subterms, fixity) =>
|
||||
if subterms.len() == 1 && name.as_str() == "$call_with_default_policy" {
|
||||
self.to_query_term(indices, *subterms.pop().unwrap())
|
||||
.map(|mut query_term| {
|
||||
query_term.set_default_caller();
|
||||
query_term
|
||||
})
|
||||
} else {
|
||||
self.to_query_term(indices, Term::Clause(r, name, subterms, fixity))
|
||||
},
|
||||
_ => self.to_query_term(indices, term)
|
||||
}
|
||||
}
|
||||
|
||||
fn setup_query(&mut self, indices: &mut CompositeIndices, terms: Vec<Box<Term>>, blocks_cuts: bool)
|
||||
-> Result<Vec<QueryTerm>, ParserError>
|
||||
{
|
||||
let mut query_terms = vec![];
|
||||
let mut work_queue = VecDeque::from(terms);
|
||||
|
||||
while let Some(term) = work_queue.pop_front() {
|
||||
let mut term = *term;
|
||||
|
||||
// a (->) clause makes up the entire query. That's what the test confirms.
|
||||
if query_terms.is_empty() && work_queue.is_empty() {
|
||||
// check for ->, inline it if found.
|
||||
if let &mut Term::Clause(_, ref name, ref mut subterms, _) = &mut term {
|
||||
if name.as_str() == "->" && subterms.len() == 2 {
|
||||
let conq = *subterms.pop().unwrap();
|
||||
let prec = *subterms.pop().unwrap();
|
||||
|
||||
self.prepend_if_then(prec, conq, &mut work_queue, blocks_cuts);
|
||||
continue;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
for mut subterm in unfold_by_str(term, ",") {
|
||||
if !blocks_cuts {
|
||||
mark_cut_variable(&mut subterm);
|
||||
}
|
||||
|
||||
query_terms.push(self.pre_query_term(indices, subterm)?);
|
||||
}
|
||||
}
|
||||
|
||||
Ok(query_terms)
|
||||
}
|
||||
|
||||
fn setup_hook(&mut self, hook: CompileTimeHook, indices: &mut CompositeIndices, term: Term)
|
||||
-> Result<CompileTimeHookCompileInfo, ParserError>
|
||||
{
|
||||
match flatten_hook(term) {
|
||||
Term::Clause(r, name, terms, _) =>
|
||||
if name == hook.name() && terms.len() == hook.arity() {
|
||||
let term = self.setup_fact(Term::Clause(r, name, terms, None))?;
|
||||
Ok((hook, PredicateClause::Fact(term), VecDeque::from(vec![])))
|
||||
} else if name.as_str() == ":-" && terms.len() == 2 {
|
||||
let rule = self.setup_rule(indices, terms, true)?;
|
||||
let results_queue = self.parse_queue(indices)?;
|
||||
|
||||
Ok((hook, PredicateClause::Rule(rule), results_queue))
|
||||
} else {
|
||||
Err(ParserError::InvalidHook)
|
||||
},
|
||||
_ => Err(ParserError::InvalidHook)
|
||||
}
|
||||
}
|
||||
|
||||
fn setup_rule(&mut self, indices: &mut CompositeIndices, mut terms: Vec<Box<Term>>,
|
||||
blocks_cuts: bool)
|
||||
-> Result<Rule, ParserError>
|
||||
{
|
||||
let post_head_terms: Vec<_> = terms.drain(1 ..).collect();
|
||||
|
||||
let head = *terms.first().cloned().unwrap();
|
||||
let tail = *post_head_terms.first().cloned().unwrap();
|
||||
|
||||
self.dynamic_clauses.push((head, tail));
|
||||
|
||||
let mut query_terms = self.setup_query(indices, post_head_terms, blocks_cuts)?;
|
||||
let clauses = query_terms.drain(1 ..).collect();
|
||||
let qt = query_terms.pop().unwrap();
|
||||
|
||||
match *terms.pop().unwrap() {
|
||||
Term::Clause(_, name, terms, _) =>
|
||||
Ok(Rule { head: (name, terms, qt), clauses }),
|
||||
Term::Constant(_, Constant::Atom(name, _)) =>
|
||||
Ok(Rule { head: (name, vec![], qt), clauses }),
|
||||
_ => Err(ParserError::InvalidRuleHead)
|
||||
}
|
||||
}
|
||||
|
||||
fn try_term_to_tl(&mut self, indices: &mut CompositeIndices, term: Term, blocks_cuts: bool)
|
||||
-> Result<TopLevel, ParserError>
|
||||
{
|
||||
match term {
|
||||
Term::Clause(r, name, mut terms, fixity) =>
|
||||
if let Some(hook) = is_compile_time_hook(&name, &terms) {
|
||||
let term = Term::Clause(r, name, terms, fixity);
|
||||
let (hook, clause, queue) = self.setup_hook(hook, indices, term)?;
|
||||
|
||||
Ok(TopLevel::Declaration(Declaration::Hook(hook, clause, queue)))
|
||||
} else if name.as_str() == "?-" {
|
||||
Ok(TopLevel::Query(try!(self.setup_query(indices, terms, blocks_cuts))))
|
||||
} else if name.as_str() == ":-" && terms.len() > 1 {
|
||||
Ok(TopLevel::Rule(try!(self.setup_rule(indices, terms, blocks_cuts))))
|
||||
} else if name.as_str() == ":-" && terms.len() == 1 {
|
||||
let term = *terms.pop().unwrap();
|
||||
Ok(TopLevel::Declaration(try!(setup_declaration(term))))
|
||||
} else {
|
||||
let term = Term::Clause(r, name, terms, fixity);
|
||||
Ok(TopLevel::Fact(try!(self.setup_fact(term))))
|
||||
},
|
||||
term => Ok(TopLevel::Fact(try!(self.setup_fact(term))))
|
||||
}
|
||||
}
|
||||
|
||||
fn try_terms_to_tls<I>(&mut self, indices: &mut CompositeIndices, terms: I, blocks_cuts: bool)
|
||||
-> Result<VecDeque<TopLevel>, ParserError>
|
||||
where I: IntoIterator<Item=Term>
|
||||
{
|
||||
let mut results = VecDeque::new();
|
||||
|
||||
for term in terms.into_iter() {
|
||||
results.push_back(self.try_term_to_tl(indices, term, blocks_cuts)?);
|
||||
}
|
||||
|
||||
Ok(results)
|
||||
}
|
||||
|
||||
fn parse_queue(&mut self, indices: &mut CompositeIndices) -> Result<VecDeque<TopLevel>, ParserError>
|
||||
{
|
||||
let mut queue = VecDeque::new();
|
||||
|
||||
while let Some(terms) = self.queue.pop_front() {
|
||||
let clauses = merge_clauses(&mut self.try_terms_to_tls(indices, terms, false)?)?;
|
||||
queue.push_back(clauses);
|
||||
}
|
||||
|
||||
Ok(queue)
|
||||
}
|
||||
|
||||
fn absorb(&mut self, other: RelationWorker) {
|
||||
self.queue.extend(other.queue.into_iter());
|
||||
self.dynamic_clauses.extend(other.dynamic_clauses.into_iter());
|
||||
}
|
||||
|
||||
fn expand_queue_contents<'a, R>(&mut self, term_stream: &mut TermStream<'a, R>, op_dir: &OpDir)
|
||||
-> Result<(), SessionError>
|
||||
where R: Read
|
||||
{
|
||||
let mut machine_st = MachineState::new();
|
||||
let mut new_queue = VecDeque::new();
|
||||
|
||||
while let Some(terms) = self.queue.pop_front() {
|
||||
let mut new_terms = VecDeque::new();
|
||||
|
||||
for term in terms {
|
||||
new_terms.push_back(term_stream.run_goal_expanders(&mut machine_st, &op_dir, term)?);
|
||||
}
|
||||
|
||||
new_queue.push_back(new_terms);
|
||||
}
|
||||
|
||||
Ok(self.queue = new_queue)
|
||||
}
|
||||
}
|
||||
|
||||
fn term_to_toplevel<'a, R>(term_stream: &mut TermStream<'a, R>, code_dir: &mut CodeDir, term: Term)
|
||||
-> Result<(TopLevel, RelationWorker), ParserError>
|
||||
where R: Read
|
||||
{
|
||||
let mut rel_worker = RelationWorker::new();
|
||||
let mut indices = composite_indices!(false, term_stream.indices, code_dir);
|
||||
|
||||
let tl = rel_worker.try_term_to_tl(&mut indices, term, true)?;
|
||||
Ok((tl, rel_worker))
|
||||
}
|
||||
|
||||
pub
|
||||
fn string_to_toplevel<R: Read>(src: R, buffer: String, wam: &mut Machine)
|
||||
-> Result<TopLevelPacket, SessionError>
|
||||
{
|
||||
let mut term_stream = TermStream::new(src, wam.indices.atom_tbl(),
|
||||
wam.machine_flags(), &mut wam.indices,
|
||||
&mut wam.policies, &mut wam.code_repo);
|
||||
|
||||
term_stream.add_to_top(buffer.as_str());
|
||||
|
||||
let term = term_stream.read_term(&OpDir::new())?;
|
||||
let mut code_dir = CodeDir::new();
|
||||
|
||||
let (tl, mut rel_worker) = term_to_toplevel(&mut term_stream, &mut code_dir, term)?;
|
||||
|
||||
rel_worker.expand_queue_contents(&mut term_stream, &OpDir::new())?;
|
||||
|
||||
let mut indices = composite_indices!(false, term_stream.indices, &mut code_dir);
|
||||
let queue = rel_worker.parse_queue(&mut indices)?;
|
||||
|
||||
Ok(deque_to_packet(tl, queue))
|
||||
}
|
||||
|
||||
pub type DynamicClauseMap = HashMap<(ClauseName, usize), Vec<(Term, Term)>>;
|
||||
|
||||
pub struct TopLevelBatchWorker<'a, R: Read> {
|
||||
pub(crate) term_stream: TermStream<'a, R>,
|
||||
rel_worker: RelationWorker,
|
||||
pub(crate) results: Vec<(Predicate, VecDeque<TopLevel>)>,
|
||||
pub(crate) dynamic_clause_map: DynamicClauseMap,
|
||||
pub(crate) in_module: bool
|
||||
}
|
||||
|
||||
impl<'a, R: Read> TopLevelBatchWorker<'a, R> {
|
||||
pub fn new(inner: R, atom_tbl: TabledData<Atom>,
|
||||
flags: MachineFlags, indices: &'a mut IndexStore,
|
||||
policies: &'a mut MachinePolicies, code_repo: &'a mut CodeRepo)
|
||||
-> Self
|
||||
{
|
||||
let term_stream = TermStream::new(inner, atom_tbl, flags,
|
||||
indices, policies, code_repo);
|
||||
|
||||
TopLevelBatchWorker { term_stream,
|
||||
rel_worker: RelationWorker::new(),
|
||||
results: vec![],
|
||||
dynamic_clause_map: HashMap::new(),
|
||||
in_module: false }
|
||||
}
|
||||
|
||||
fn try_term_to_tl(&self, indices: &mut IndexStore, term: Term)
|
||||
-> Result<(TopLevel, RelationWorker), SessionError>
|
||||
{
|
||||
let mut new_rel_worker = RelationWorker::new();
|
||||
let mut indices = composite_indices!(self.in_module, indices,
|
||||
&self.term_stream.indices.code_dir);
|
||||
|
||||
Ok((new_rel_worker.try_term_to_tl(&mut indices, term, true)?, new_rel_worker))
|
||||
}
|
||||
|
||||
fn process_result(&mut self, indices: &mut IndexStore, preds: &mut Vec<PredicateClause>)
|
||||
-> Result<(), SessionError>
|
||||
{
|
||||
self.rel_worker.expand_queue_contents(&mut self.term_stream, &indices.op_dir)?;
|
||||
|
||||
let mut indices = composite_indices!(self.in_module, indices,
|
||||
&mut self.term_stream.indices.code_dir);
|
||||
|
||||
let queue = self.rel_worker.parse_queue(&mut indices)?;
|
||||
let result = (append_preds(preds), queue);
|
||||
|
||||
let in_situ_code_dir = &mut self.term_stream.indices.in_situ_code_dir;
|
||||
|
||||
self.term_stream.code_repo.add_in_situ_result(&result, in_situ_code_dir,
|
||||
self.term_stream.flags)?;
|
||||
|
||||
Ok(self.results.push(result))
|
||||
}
|
||||
|
||||
fn take_dynamic_clauses(&mut self) {
|
||||
let (name, arity) = match self.rel_worker.dynamic_clauses.first() {
|
||||
Some((head, _)) =>
|
||||
(head.name().unwrap(), head.arity()),
|
||||
None =>
|
||||
return
|
||||
};
|
||||
|
||||
match self.dynamic_clause_map.get_mut(&(name.clone(), arity)) {
|
||||
Some(ref mut entry) => {
|
||||
entry.clear(); // don't treat dynamic predicates as if they're discontiguous.
|
||||
entry.extend(self.rel_worker.dynamic_clauses.drain(0 ..));
|
||||
},
|
||||
_ => {
|
||||
self.rel_worker.dynamic_clauses.clear();
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
pub fn consume(&mut self, indices: &mut IndexStore) -> Result<Option<Declaration>, SessionError>
|
||||
{
|
||||
let mut preds = vec![];
|
||||
|
||||
while !self.term_stream.eof()? {
|
||||
let term = self.term_stream.read_term(&indices.op_dir)?;
|
||||
let (tl, new_rel_worker) = self.try_term_to_tl(indices, term)?;
|
||||
|
||||
// if is_consistent is false, preds is non-empty.
|
||||
if !is_consistent(&tl, &preds) {
|
||||
self.process_result(indices, &mut preds)?;
|
||||
self.take_dynamic_clauses();
|
||||
}
|
||||
|
||||
self.rel_worker.absorb(new_rel_worker);
|
||||
|
||||
match tl {
|
||||
TopLevel::Fact(fact) => preds.push(PredicateClause::Fact(fact)),
|
||||
TopLevel::Rule(rule) => preds.push(PredicateClause::Rule(rule)),
|
||||
TopLevel::Predicate(pred) => preds.extend(pred.0),
|
||||
TopLevel::Declaration(decl) => return Ok(Some(decl)),
|
||||
TopLevel::Query(_) => return Err(SessionError::NamelessEntry)
|
||||
}
|
||||
}
|
||||
|
||||
if !preds.is_empty() {
|
||||
self.process_result(indices, &mut preds)?;
|
||||
self.take_dynamic_clauses();
|
||||
}
|
||||
|
||||
Ok(None)
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user