rishi/scryer-prolog
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

simply post order iterators.

Browse Source
This commit is contained in:
Mark Thom
2017-11-12 01:36:19 -07:00
parent e5a235cf80
commit e0f2ca80b5
2 changed files with 6 additions and 28 deletions
Download Patch File Download Diff File Expand all files Collapse all files

15
src/prolog/arithmetic.rs
View File

@@ -3,7 +3,6 @@ use prolog::fixtures::*;
use prolog::num::{BigInt, Zero};
use prolog::ordered_float::{OrderedFloat};
use std::cell::Cell;
use std::cmp::{min, max};
use std::vec::Vec;
@@ -12,20 +11,10 @@ pub struct ArithExprIterator<'a> {
}
impl<'a> ArithExprIterator<'a> {
fn push_clause(&mut self, child_num: usize, ct: ClauseType<'a>, child_terms: &'a Vec<Box<Term>>)
{
self.state_stack.push(IteratorState::Clause(child_num, ct, child_terms));
}
fn push_subterm(&mut self, lvl: Level, term: &'a Term) {
self.state_stack.push(IteratorState::to_state(lvl, term));
}
fn push_final_cons(&mut self, lvl: Level, cell: &'a Cell<RegType>, head: &'a Term, tail: &'a Term)
{
self.state_stack.push(IteratorState::FinalCons(lvl, cell, head, tail));
}
fn new(term: &'a Term) -> Result<Self, ArithmeticError> {
let state = match term {
&Term::AnonVar =>
@@ -62,12 +51,12 @@ impl<'a> Iterator for ArithExprIterator<'a> {
if child_num == child_terms.len() {
return Some(TermRef::Clause(ct, child_terms));
} else {
self.push_clause(child_num + 1, ct, child_terms);
self.state_stack.push(IteratorState::Clause(child_num + 1, ct, child_terms));
self.push_subterm(ct.level_of_subterms(), child_terms[child_num].as_ref());
}
},
IteratorState::InitialCons(lvl, cell, head, tail) => {
self.push_final_cons(lvl, cell, head, tail);
self.state_stack.push(IteratorState::FinalCons(lvl, cell, head, tail));
self.push_subterm(Level::Deep, tail);
self.push_subterm(Level::Deep, head);
},

19
src/prolog/iterators.rs
View File

@@ -1,6 +1,5 @@
use prolog::ast::*;
use std::cell::Cell;
use std::collections::VecDeque;
use std::iter::*;
use std::vec::Vec;
@@ -10,20 +9,10 @@ pub struct QueryIterator<'a> {
}
impl<'a> QueryIterator<'a> {
fn push_clause(&mut self, child_num: usize, ct: ClauseType<'a>, child_terms: &'a Vec<Box<Term>>)
{
self.state_stack.push(IteratorState::Clause(child_num, ct, child_terms));
}
fn push_subterm(&mut self, lvl: Level, term: &'a Term) {
self.state_stack.push(IteratorState::to_state(lvl, term));
}
fn push_final_cons(&mut self, lvl: Level, cell: &'a Cell<RegType>, head: &'a Term, tail: &'a Term)
{
self.state_stack.push(IteratorState::FinalCons(lvl, cell, head, tail));
}
fn from_term(term: &'a Term) -> Self {
let state = match term {
&Term::AnonVar =>
@@ -76,7 +65,7 @@ impl QueryTerm {
impl<'a> Iterator for QueryIterator<'a> {
type Item = TermRef<'a>;
fn next(&mut self) -> Option<Self::Item> {
while let Some(iter_state) = self.state_stack.pop() {
match iter_state {
@@ -93,12 +82,12 @@ impl<'a> Iterator for QueryIterator<'a> {
return None
};
} else {
self.push_clause(child_num + 1, ct, child_terms);
self.state_stack.push(IteratorState::Clause(child_num + 1, ct, child_terms));
self.push_subterm(ct.level_of_subterms(), child_terms[child_num].as_ref());
}
},
IteratorState::InitialCons(lvl, cell, head, tail) => {
self.push_final_cons(lvl, cell, head, tail);
self.state_stack.push(IteratorState::FinalCons(lvl, cell, head, tail));
self.push_subterm(Level::Deep, tail);
self.push_subterm(Level::Deep, head);
},
@@ -111,7 +100,7 @@ impl<'a> Iterator for QueryIterator<'a> {
};
}
None
None
}
}