update writer

This commit is contained in:
Mark Thom
2019-03-29 22:49:33 -06:00
parent 3aeebbe6d6
commit b45c591c89
5 changed files with 152 additions and 34 deletions

View File

@@ -1,6 +1,6 @@
[package]
name = "scryer-prolog"
version = "0.8.22"
version = "0.8.23"
authors = ["Mark Thom <markjordanthom@gmail.com>"]
repository = "https://github.com/mthom/scryer-prolog"
description = "A modern Prolog implementation written mostly in Rust."
@@ -14,7 +14,7 @@ cfg-if = "0.1.7"
downcast = "0.9.1"
num = "0.2"
ordered-float = "0.5.0"
prolog_parser = "0.8.3"
prolog_parser = "0.8.4"
readline_rs_compat = { version = "0.1.7", optional = true }
ref_thread_local = "0.0.0"

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@@ -9,8 +9,8 @@ use std::ops::Deref;
use std::vec::Vec;
pub struct HCPreOrderIterator<'a> {
machine_st: &'a MachineState,
state_stack: Vec<Addr>
pub machine_st: &'a MachineState,
pub state_stack: Vec<Addr>
}
impl<'a> HCPreOrderIterator<'a> {
@@ -24,7 +24,7 @@ impl<'a> HCPreOrderIterator<'a> {
pub fn machine_st(&self) -> &MachineState {
&self.machine_st
}
fn follow_heap(&mut self, h: usize) -> Addr
{
match &self.machine_st.heap[h] {

View File

@@ -28,9 +28,18 @@ impl DirectedOp {
name.as_str()
}
}
#[inline]
fn is_negative_sign(&self) -> bool {
match self {
&DirectedOp::Left(ref name, (_, spec)) | &DirectedOp::Right(ref name, (_, spec)) =>
name.as_str() == "-" && is_prefix!(spec)
}
}
}
fn needs_bracketing(child_spec: (usize, Specifier), op: &DirectedOp) -> bool {
fn needs_bracketing(child_spec: (usize, Specifier), op: &DirectedOp) -> bool
{
match op {
&DirectedOp::Left(_, (priority, spec)) => {
let is_strict_right = is_yfx!(spec) || is_xfx!(spec) || is_fx!(spec);
@@ -43,6 +52,45 @@ fn needs_bracketing(child_spec: (usize, Specifier), op: &DirectedOp) -> bool {
}
}
impl<'a> HCPreOrderIterator<'a> {
/*
* descend into the subtree where the iterator is currently parked
* and check that the leftmost leaf is a number, with every node
* encountered on the way an infix or postfix operator, and not blocked
* by brackets.
*/
fn leftmost_leaf_is_positive_number(&self) -> bool {
let mut addr = match self.state_stack.last().cloned() {
Some(addr) => addr,
None => return false
};
let mut parent_spec = DirectedOp::Left(clause_name!("-"), (200, FY));
loop {
match self.machine_st.store(self.machine_st.deref(addr)) {
Addr::Str(s) =>
match &self.machine_st.heap[s] {
&HeapCellValue::NamedStr(_, ref name, Some(spec))
if is_postfix!(spec.1) || is_infix!(spec.1) =>
if needs_bracketing(spec, &parent_spec) {
return false;
} else {
addr = Addr::HeapCell(s+1);
parent_spec = DirectedOp::Right(name.clone(), spec);
},
_ =>
return false
},
Addr::Con(Constant::Number(n)) =>
return n.is_positive(),
_ =>
return false
}
}
}
}
#[derive(Clone)]
pub enum TokenOrRedirect {
Atom(ClauseName),
@@ -53,6 +101,9 @@ pub enum TokenOrRedirect {
Open,
Close,
Comma,
Space,
LeftCurly,
RightCurly,
OpenList(Rc<Cell<bool>>),
CloseList(Rc<Cell<bool>>),
HeadTailSeparator,
@@ -137,6 +188,16 @@ fn is_numbered_var(ct: &ClauseType, arity: usize) -> bool {
}
}
#[inline]
fn negated_op_needs_bracketing(iter: &HCPreOrderIterator, op: &Option<DirectedOp>) -> bool
{
if let &Some(ref op) = op {
op.is_negative_sign() && iter.leftmost_leaf_is_positive_number()
} else {
false
}
}
impl MachineState {
pub fn numbervar(&self, offset: &BigInt, addr: Addr) -> Option<Var> {
static CHAR_CODES: [char; 26] = ['A','B','C','D','E','F','G','H','I','J',
@@ -181,8 +242,10 @@ pub struct HCPrinter<'a, Outputter> {
macro_rules! push_space_if_amb {
($self:expr, $atom:expr, $action:block) => (
if $self.ambiguity_check($atom) {
if !$self.outputter.range(0 .. $self.last_item_idx).ends_with(" ") {
$self.outputter.insert($self.last_item_idx, ' ');
if $self.last_item_idx > 1 {
if !$self.outputter.range(0 .. $self.last_item_idx).ends_with(" ") {
$self.outputter.insert($self.last_item_idx, ' ');
}
}
$self.outputter.push_char(' ');
@@ -314,6 +377,7 @@ impl<'a, Outputter: HCValueOutputter> HCPrinter<'a, Outputter>
continues_with_append(tail, atom)
}
// TODO: create a DirectedOp factory method. Use it here, and above.
fn enqueue_op(&mut self, ct: ClauseType, spec: (usize, Specifier)) {
if is_postfix!(spec.1) {
let right_directed_op = DirectedOp::Right(ct.name(), spec);
@@ -321,6 +385,11 @@ impl<'a, Outputter: HCValueOutputter> HCPrinter<'a, Outputter>
self.state_stack.push(TokenOrRedirect::Op(ct.name(), spec));
self.state_stack.push(TokenOrRedirect::CompositeRedirect(right_directed_op));
} else if is_prefix!(spec.1) {
if ct.name().as_str() == "-" {
self.format_negated_operand();
return;
}
let left_directed_op = DirectedOp::Left(ct.name(), spec);
self.state_stack.push(TokenOrRedirect::CompositeRedirect(left_directed_op));
@@ -350,6 +419,22 @@ impl<'a, Outputter: HCValueOutputter> HCPrinter<'a, Outputter>
self.state_stack.push(TokenOrRedirect::Atom(name));
}
fn format_negated_operand(&mut self)
{
let op = DirectedOp::Left(clause_name!("-"), (200, FY));
self.state_stack.push(TokenOrRedirect::CompositeRedirect(op));
self.state_stack.push(TokenOrRedirect::Space);
self.state_stack.push(TokenOrRedirect::Atom(clause_name!("-")));
}
fn format_curly_braces(&mut self)
{
self.state_stack.push(TokenOrRedirect::RightCurly);
self.state_stack.push(TokenOrRedirect::FunctorRedirect);
self.state_stack.push(TokenOrRedirect::LeftCurly);
}
fn format_clause(&mut self, iter: &mut HCPreOrderIterator, arity: usize, ct: ClauseType)
{
if let Some(spec) = ct.spec() {
@@ -367,7 +452,11 @@ impl<'a, Outputter: HCValueOutputter> HCPrinter<'a, Outputter>
}
}
self.format_struct(arity, ct.name());
match (ct.name().as_str(), arity) {
("-", 1) => self.format_negated_operand(),
("{}", 1) => self.format_curly_braces(),
_ => self.format_struct(arity, ct.name())
};
}
#[inline]
@@ -476,6 +565,45 @@ impl<'a, Outputter: HCValueOutputter> HCPrinter<'a, Outputter>
};
}
fn print_number(&mut self, n: Number, op: &Option<DirectedOp>) {
let add_brackets = if let Some(op) = op {
op.is_negative_sign() && n.is_positive()
} else {
false
};
if add_brackets {
self.push_char('(');
}
match n {
Number::Float(fl) =>
if &fl == &OrderedFloat(0f64) {
push_space_if_amb!(self, "0", {
self.append_str("0");
});
} else {
let OrderedFloat(fl) = fl;
let output_str = format!("{0:<20?}", fl);
push_space_if_amb!(self, &output_str, {
self.append_str(&output_str.trim());
});
},
n => {
let output_str = format!("{}", n);
push_space_if_amb!(self, &output_str, {
self.append_str(&output_str);
});
}
}
if add_brackets {
self.push_char(')');
}
}
fn print_constant(&mut self, c: Constant, op: &Option<DirectedOp>) {
match c {
Constant::Atom(ref atom, Some(spec)) => {
@@ -509,26 +637,8 @@ impl<'a, Outputter: HCValueOutputter> HCPrinter<'a, Outputter>
},
Constant::EmptyList =>
self.append_str("[]"),
Constant::Number(Number::Float(fl)) =>
if &fl == &OrderedFloat(0f64) {
push_space_if_amb!(self, "0", {
self.append_str("0");
});
} else {
let OrderedFloat(fl) = fl;
let output_str = format!("{0:<20?}", fl);
push_space_if_amb!(self, &output_str, {
self.append_str(&output_str.trim());
});
},
Constant::Number(n) => {
let output_str = format!("{}", n);
push_space_if_amb!(self, &output_str, {
self.append_str(&output_str);
});
},
Constant::Number(n) =>
self.print_number(n, op),
Constant::String(s) =>
if self.machine_st.machine_flags().double_quotes.is_chars() {
if !s.is_empty() {
@@ -571,6 +681,8 @@ impl<'a, Outputter: HCValueOutputter> HCPrinter<'a, Outputter>
fn handle_heap_term(&mut self, iter: &mut HCPreOrderIterator, op: Option<DirectedOp>,
is_functor_redirect: bool)
{
let add_brackets = negated_op_needs_bracketing(iter, &op);
let heap_val = match self.check_for_seen(iter) {
Some(heap_val) => heap_val,
None => return
@@ -579,7 +691,7 @@ impl<'a, Outputter: HCValueOutputter> HCPrinter<'a, Outputter>
match heap_val {
HeapCellValue::NamedStr(arity, ref name, Some(spec)) => {
let add_brackets = if !self.ignore_ops {
if let Some(ref op) = &op {
add_brackets || if let Some(ref op) = &op {
needs_bracketing(spec, op)
} else {
is_functor_redirect && spec.0 >= 1000
@@ -604,7 +716,7 @@ impl<'a, Outputter: HCValueOutputter> HCPrinter<'a, Outputter>
let ct = ClauseType::from(name, 0, fixity);
self.format_clause(iter, 0, ct);
}),
HeapCellValue::NamedStr(arity, name, fixity) => {
HeapCellValue::NamedStr(arity, name, fixity) => {
let ct = ClauseType::from(name, arity, fixity);
self.format_clause(iter, arity, ct);
},
@@ -675,7 +787,13 @@ impl<'a, Outputter: HCValueOutputter> HCPrinter<'a, Outputter>
TokenOrRedirect::HeadTailSeparator =>
self.append_str(" | "),
TokenOrRedirect::Comma =>
self.append_str(", ")
self.append_str(", "),
TokenOrRedirect::Space =>
self.push_char(' '),
TokenOrRedirect::LeftCurly =>
self.push_char('{'),
TokenOrRedirect::RightCurly =>
self.push_char('}'),
}
} else if !iter.stack().is_empty() {
let spec = self.toplevel_spec.take();

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@@ -388,7 +388,7 @@ findall(Template, Goal, Solutions) :-
Error,
( truncate_lh_to(LhLength), throw(Error) ))).
:- non_counted_backtracking '$iterate_find_all_diff'/4.
:- non_counted_backtracking '$iterate_find_all_diff'/5.
'$iterate_find_all_diff'(Template, Goal, _, _, LhOffset) :-
call(Goal),
'$copy_to_lh'(LhOffset, Template),

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@@ -117,7 +117,7 @@ pub mod readline
if let LineMode::Single = LINE_MODE {
insert_text_rl("?- ");
}
0
}