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-rw-r--r--dhall/src/semantics/core/value.rs4
-rw-r--r--dhall/src/semantics/mod.rs1
-rw-r--r--dhall/src/semantics/nze/env.rs87
-rw-r--r--dhall/src/semantics/nze/mod.rs4
-rw-r--r--dhall/src/semantics/nze/nzexpr.rs116
-rw-r--r--dhall/src/semantics/phase/normalize.rs62
-rw-r--r--dhall/src/semantics/phase/typecheck.rs3
-rw-r--r--dhall/src/semantics/tck/env.rs137
-rw-r--r--dhall/src/semantics/tck/mod.rs2
-rw-r--r--dhall/src/semantics/tck/tyexpr.rs6
-rw-r--r--dhall/src/semantics/tck/typecheck.rs58
11 files changed, 239 insertions, 241 deletions
diff --git a/dhall/src/semantics/core/value.rs b/dhall/src/semantics/core/value.rs
index 90b30b4..7334552 100644
--- a/dhall/src/semantics/core/value.rs
+++ b/dhall/src/semantics/core/value.rs
@@ -4,12 +4,12 @@ use std::rc::Rc;
use crate::error::{TypeError, TypeMessage};
use crate::semantics::core::var::{AlphaVar, Binder};
-use crate::semantics::nze::{NzVar, VarEnv};
-use crate::semantics::phase::normalize::{apply_any, normalize_whnf, NzEnv};
+use crate::semantics::phase::normalize::{apply_any, normalize_whnf};
use crate::semantics::phase::typecheck::{
builtin_to_value, builtin_to_value_env, const_to_value,
};
use crate::semantics::phase::{Normalized, NormalizedExpr, ToExprOptions};
+use crate::semantics::{NzEnv, NzVar, VarEnv};
use crate::semantics::{TyExpr, TyExprKind};
use crate::syntax::{
BinOp, Builtin, Const, ExprKind, Integer, InterpolatedTextContents, Label,
diff --git a/dhall/src/semantics/mod.rs b/dhall/src/semantics/mod.rs
index 1304502..ce08334 100644
--- a/dhall/src/semantics/mod.rs
+++ b/dhall/src/semantics/mod.rs
@@ -3,4 +3,5 @@ pub mod nze;
pub mod phase;
pub mod tck;
pub(crate) use self::core::*;
+pub(crate) use self::nze::*;
pub(crate) use self::tck::*;
diff --git a/dhall/src/semantics/nze/env.rs b/dhall/src/semantics/nze/env.rs
new file mode 100644
index 0000000..203d99a
--- /dev/null
+++ b/dhall/src/semantics/nze/env.rs
@@ -0,0 +1,87 @@
+use crate::semantics::{AlphaVar, TyEnv, Value, ValueKind};
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub(crate) enum NzVar {
+ /// Reverse-debruijn index: counts number of binders from the bottom of the stack.
+ Bound(usize),
+ /// Fake fresh variable generated for expression equality checking.
+ Fresh(usize),
+}
+
+#[derive(Debug, Clone)]
+pub(crate) enum NzEnvItem {
+ // Variable is bound with given type
+ Kept(Value),
+ // Variable has been replaced by corresponding value
+ Replaced(Value),
+}
+
+#[derive(Debug, Clone)]
+pub(crate) struct NzEnv {
+ items: Vec<NzEnvItem>,
+}
+
+impl NzVar {
+ pub fn new(idx: usize) -> Self {
+ NzVar::Bound(idx)
+ }
+ pub fn fresh() -> Self {
+ use std::sync::atomic::{AtomicUsize, Ordering};
+ // Global counter to ensure uniqueness of the generated id.
+ static FRESH_VAR_COUNTER: AtomicUsize = AtomicUsize::new(0);
+ let id = FRESH_VAR_COUNTER.fetch_add(1, Ordering::SeqCst);
+ NzVar::Fresh(id)
+ }
+ /// Get index of bound variable.
+ /// Panics on a fresh variable.
+ pub fn idx(&self) -> usize {
+ match self {
+ NzVar::Bound(i) => *i,
+ NzVar::Fresh(_) => panic!(
+ "Trying to use a fresh variable outside of equality checking"
+ ),
+ }
+ }
+}
+
+impl NzEnv {
+ pub fn new() -> Self {
+ NzEnv { items: Vec::new() }
+ }
+ pub fn to_alpha_tyenv(&self) -> TyEnv {
+ TyEnv::from_nzenv_alpha(self)
+ }
+
+ pub fn insert_type(&self, t: Value) -> Self {
+ let mut env = self.clone();
+ env.items.push(NzEnvItem::Kept(t));
+ env
+ }
+ pub fn insert_value(&self, e: Value) -> Self {
+ let mut env = self.clone();
+ env.items.push(NzEnvItem::Replaced(e));
+ env
+ }
+ pub fn lookup_val(&self, var: &AlphaVar) -> Value {
+ let idx = self.items.len() - 1 - var.idx();
+ match &self.items[idx] {
+ NzEnvItem::Kept(ty) => Value::from_kind_and_type_whnf(
+ ValueKind::Var(var.clone(), NzVar::new(idx)),
+ ty.clone(),
+ ),
+ NzEnvItem::Replaced(x) => x.clone(),
+ }
+ }
+
+ pub fn size(&self) -> usize {
+ self.items.len()
+ }
+}
+
+/// Ignore NzEnv when comparing; useful because we store them in `AppliedBuiltin`.
+impl std::cmp::PartialEq for NzEnv {
+ fn eq(&self, _other: &Self) -> bool {
+ true
+ }
+}
+impl std::cmp::Eq for NzEnv {}
diff --git a/dhall/src/semantics/nze/mod.rs b/dhall/src/semantics/nze/mod.rs
index 213404c..1cd2363 100644
--- a/dhall/src/semantics/nze/mod.rs
+++ b/dhall/src/semantics/nze/mod.rs
@@ -1,2 +1,2 @@
-pub mod nzexpr;
-pub(crate) use nzexpr::*;
+pub mod env;
+pub(crate) use env::*;
diff --git a/dhall/src/semantics/nze/nzexpr.rs b/dhall/src/semantics/nze/nzexpr.rs
deleted file mode 100644
index c065a5b..0000000
--- a/dhall/src/semantics/nze/nzexpr.rs
+++ /dev/null
@@ -1,116 +0,0 @@
-use crate::semantics::core::var::AlphaVar;
-use crate::syntax::{Label, V};
-
-pub(crate) type Binder = Label;
-
-#[derive(Debug, Clone)]
-pub(crate) struct NameEnv {
- names: Vec<Binder>,
-}
-
-#[derive(Debug, Clone, Copy)]
-pub(crate) struct VarEnv {
- size: usize,
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq)]
-pub(crate) enum NzVar {
- /// Reverse-debruijn index: counts number of binders from the bottom of the stack.
- Bound(usize),
- /// Fake fresh variable generated for expression equality checking.
- Fresh(usize),
-}
-
-impl NameEnv {
- pub fn new() -> Self {
- NameEnv { names: Vec::new() }
- }
- pub fn from_binders(names: impl Iterator<Item = Binder>) -> Self {
- NameEnv {
- names: names.collect(),
- }
- }
- pub fn as_varenv(&self) -> VarEnv {
- VarEnv {
- size: self.names.len(),
- }
- }
-
- pub fn insert(&self, x: &Binder) -> Self {
- let mut env = self.clone();
- env.insert_mut(x);
- env
- }
- pub fn insert_mut(&mut self, x: &Binder) {
- self.names.push(x.clone())
- }
- pub fn remove_mut(&mut self) {
- self.names.pop();
- }
-
- pub fn unlabel_var(&self, var: &V<Binder>) -> Option<AlphaVar> {
- let V(name, idx) = var;
- let (idx, _) = self
- .names
- .iter()
- .rev()
- .enumerate()
- .filter(|(_, n)| *n == name)
- .nth(*idx)?;
- Some(AlphaVar::new(V((), idx)))
- }
- pub fn label_var(&self, var: &AlphaVar) -> V<Binder> {
- let name = &self.names[self.names.len() - 1 - var.idx()];
- let idx = self
- .names
- .iter()
- .rev()
- .take(var.idx())
- .filter(|n| *n == name)
- .count();
- V(name.clone(), idx)
- }
-}
-
-impl VarEnv {
- pub fn new() -> Self {
- VarEnv { size: 0 }
- }
- pub fn size(&self) -> usize {
- self.size
- }
- pub fn insert(&self) -> Self {
- VarEnv {
- size: self.size + 1,
- }
- }
- pub fn lookup(&self, var: &NzVar) -> AlphaVar {
- self.lookup_fallible(var).unwrap()
- }
- pub fn lookup_fallible(&self, var: &NzVar) -> Option<AlphaVar> {
- let idx = self.size.checked_sub(var.idx() + 1)?;
- Some(AlphaVar::new(V((), idx)))
- }
-}
-
-impl NzVar {
- pub fn new(idx: usize) -> Self {
- NzVar::Bound(idx)
- }
- pub fn fresh() -> Self {
- use std::sync::atomic::{AtomicUsize, Ordering};
- // Global counter to ensure uniqueness of the generated id.
- static FRESH_VAR_COUNTER: AtomicUsize = AtomicUsize::new(0);
- let id = FRESH_VAR_COUNTER.fetch_add(1, Ordering::SeqCst);
- NzVar::Fresh(id)
- }
- // Panics on a fresh variable.
- pub fn idx(&self) -> usize {
- match self {
- NzVar::Bound(i) => *i,
- NzVar::Fresh(_) => panic!(
- "Trying to use a fresh variable outside of equality checking"
- ),
- }
- }
-}
diff --git a/dhall/src/semantics/phase/normalize.rs b/dhall/src/semantics/phase/normalize.rs
index fa80b6e..ce37993 100644
--- a/dhall/src/semantics/phase/normalize.rs
+++ b/dhall/src/semantics/phase/normalize.rs
@@ -1,16 +1,13 @@
use std::collections::HashMap;
use std::convert::TryInto;
-use crate::semantics::nze::NzVar;
use crate::semantics::phase::typecheck::{
builtin_to_value_env, const_to_value, rc,
};
use crate::semantics::phase::Normalized;
use crate::semantics::tck::typecheck::type_with;
-use crate::semantics::tck::typecheck::TyEnv;
-use crate::semantics::{
- AlphaVar, Binder, Closure, TyExpr, TyExprKind, Value, ValueKind,
-};
+use crate::semantics::NzEnv;
+use crate::semantics::{Binder, Closure, TyExpr, TyExprKind, Value, ValueKind};
use crate::syntax;
use crate::syntax::Const::Type;
use crate::syntax::{
@@ -838,53 +835,6 @@ pub(crate) fn normalize_whnf(
}
}
-#[derive(Debug, Clone)]
-pub(crate) enum NzEnvItem {
- // Variable is bound with given type
- Kept(Value),
- // Variable has been replaced by corresponding value
- Replaced(Value),
-}
-
-#[derive(Debug, Clone)]
-pub(crate) struct NzEnv {
- items: Vec<NzEnvItem>,
-}
-
-impl NzEnv {
- pub fn new() -> Self {
- NzEnv { items: Vec::new() }
- }
- pub fn to_alpha_tyenv(&self) -> TyEnv {
- TyEnv::from_nzenv_alpha(self)
- }
-
- pub fn insert_type(&self, t: Value) -> Self {
- let mut env = self.clone();
- env.items.push(NzEnvItem::Kept(t));
- env
- }
- pub fn insert_value(&self, e: Value) -> Self {
- let mut env = self.clone();
- env.items.push(NzEnvItem::Replaced(e));
- env
- }
- pub fn lookup_val(&self, var: &AlphaVar) -> Value {
- let idx = self.items.len() - 1 - var.idx();
- match &self.items[idx] {
- NzEnvItem::Kept(ty) => Value::from_kind_and_type_whnf(
- ValueKind::Var(var.clone(), NzVar::new(idx)),
- ty.clone(),
- ),
- NzEnvItem::Replaced(x) => x.clone(),
- }
- }
-
- pub fn size(&self) -> usize {
- self.items.len()
- }
-}
-
/// Normalize a TyExpr into WHNF
pub(crate) fn normalize_tyexpr_whnf(tye: &TyExpr, env: &NzEnv) -> Value {
let ty = match tye.get_type() {
@@ -924,11 +874,3 @@ pub(crate) fn normalize_tyexpr_whnf(tye: &TyExpr, env: &NzEnv) -> Value {
// dbg!(tye.kind(), env, &kind);
Value::from_kind_and_type_whnf(kind, ty)
}
-
-/// Ignore NzEnv when comparing
-impl std::cmp::PartialEq for NzEnv {
- fn eq(&self, _other: &Self) -> bool {
- true
- }
-}
-impl std::cmp::Eq for NzEnv {}
diff --git a/dhall/src/semantics/phase/typecheck.rs b/dhall/src/semantics/phase/typecheck.rs
index 4392365..2e22ad2 100644
--- a/dhall/src/semantics/phase/typecheck.rs
+++ b/dhall/src/semantics/phase/typecheck.rs
@@ -1,5 +1,4 @@
-use crate::semantics::phase::normalize::NzEnv;
-use crate::semantics::{Value, ValueKind};
+use crate::semantics::{NzEnv, Value, ValueKind};
use crate::syntax;
use crate::syntax::{
Builtin, Const, Expr, ExprKind, Label, Span, UnspannedExpr,
diff --git a/dhall/src/semantics/tck/env.rs b/dhall/src/semantics/tck/env.rs
new file mode 100644
index 0000000..32c2f21
--- /dev/null
+++ b/dhall/src/semantics/tck/env.rs
@@ -0,0 +1,137 @@
+use crate::semantics::{AlphaVar, NzEnv, NzVar, TyExprKind, Type, Value};
+use crate::syntax::{Label, V};
+
+/// Environment for indexing variables.
+#[derive(Debug, Clone, Copy)]
+pub(crate) struct VarEnv {
+ size: usize,
+}
+
+/// Environment for resolving names.
+#[derive(Debug, Clone)]
+pub(crate) struct NameEnv {
+ names: Vec<Label>,
+}
+
+/// Environment for typing expressions.
+#[derive(Debug, Clone)]
+pub(crate) struct TyEnv {
+ names: NameEnv,
+ items: NzEnv,
+}
+
+impl VarEnv {
+ pub fn new() -> Self {
+ VarEnv { size: 0 }
+ }
+ pub fn size(&self) -> usize {
+ self.size
+ }
+ pub fn insert(&self) -> Self {
+ VarEnv {
+ size: self.size + 1,
+ }
+ }
+ pub fn lookup(&self, var: &NzVar) -> AlphaVar {
+ self.lookup_fallible(var).unwrap()
+ }
+ pub fn lookup_fallible(&self, var: &NzVar) -> Option<AlphaVar> {
+ let idx = self.size.checked_sub(var.idx() + 1)?;
+ Some(AlphaVar::new(V((), idx)))
+ }
+}
+
+impl NameEnv {
+ pub fn new() -> Self {
+ NameEnv { names: Vec::new() }
+ }
+ pub fn from_binders(names: impl Iterator<Item = Label>) -> Self {
+ NameEnv {
+ names: names.collect(),
+ }
+ }
+ pub fn as_varenv(&self) -> VarEnv {
+ VarEnv {
+ size: self.names.len(),
+ }
+ }
+
+ pub fn insert(&self, x: &Label) -> Self {
+ let mut env = self.clone();
+ env.insert_mut(x);
+ env
+ }
+ pub fn insert_mut(&mut self, x: &Label) {
+ self.names.push(x.clone())
+ }
+ pub fn remove_mut(&mut self) {
+ self.names.pop();
+ }
+
+ pub fn unlabel_var(&self, var: &V<Label>) -> Option<AlphaVar> {
+ let V(name, idx) = var;
+ let (idx, _) = self
+ .names
+ .iter()
+ .rev()
+ .enumerate()
+ .filter(|(_, n)| *n == name)
+ .nth(*idx)?;
+ Some(AlphaVar::new(V((), idx)))
+ }
+ pub fn label_var(&self, var: &AlphaVar) -> V<Label> {
+ let name = &self.names[self.names.len() - 1 - var.idx()];
+ let idx = self
+ .names
+ .iter()
+ .rev()
+ .take(var.idx())
+ .filter(|n| *n == name)
+ .count();
+ V(name.clone(), idx)
+ }
+}
+
+impl TyEnv {
+ pub fn new() -> Self {
+ TyEnv {
+ names: NameEnv::new(),
+ items: NzEnv::new(),
+ }
+ }
+ pub fn from_nzenv_alpha(items: &NzEnv) -> Self {
+ TyEnv {
+ names: NameEnv::from_binders(
+ std::iter::repeat("_".into()).take(items.size()),
+ ),
+ items: items.clone(),
+ }
+ }
+ pub fn as_varenv(&self) -> VarEnv {
+ self.names.as_varenv()
+ }
+ pub fn as_nzenv(&self) -> &NzEnv {
+ &self.items
+ }
+ pub fn as_nameenv(&self) -> &NameEnv {
+ &self.names
+ }
+
+ pub fn insert_type(&self, x: &Label, t: Type) -> Self {
+ TyEnv {
+ names: self.names.insert(x),
+ items: self.items.insert_type(t),
+ }
+ }
+ pub fn insert_value(&self, x: &Label, e: Value) -> Self {
+ TyEnv {
+ names: self.names.insert(x),
+ items: self.items.insert_value(e),
+ }
+ }
+ pub fn lookup(&self, var: &V<Label>) -> Option<(TyExprKind, Type)> {
+ let var = self.names.unlabel_var(var)?;
+ let ty = self.items.lookup_val(&var).get_type().unwrap();
+ Some((TyExprKind::Var(var), ty))
+ }
+}
diff --git a/dhall/src/semantics/tck/mod.rs b/dhall/src/semantics/tck/mod.rs
index ba95847..28974af 100644
--- a/dhall/src/semantics/tck/mod.rs
+++ b/dhall/src/semantics/tck/mod.rs
@@ -1,4 +1,6 @@
pub mod context;
+pub mod env;
pub mod tyexpr;
pub mod typecheck;
+pub(crate) use env::*;
pub(crate) use tyexpr::*;
diff --git a/dhall/src/semantics/tck/tyexpr.rs b/dhall/src/semantics/tck/tyexpr.rs
index b64c519..262cda6 100644
--- a/dhall/src/semantics/tck/tyexpr.rs
+++ b/dhall/src/semantics/tck/tyexpr.rs
@@ -1,12 +1,10 @@
use crate::error::{TypeError, TypeMessage};
use crate::semantics::core::var::AlphaVar;
-use crate::semantics::nze::nzexpr::NameEnv;
-use crate::semantics::phase::normalize::{normalize_tyexpr_whnf, NzEnv};
+use crate::semantics::phase::normalize::normalize_tyexpr_whnf;
use crate::semantics::phase::typecheck::rc;
use crate::semantics::phase::Normalized;
use crate::semantics::phase::{NormalizedExpr, ToExprOptions};
-use crate::semantics::tck::typecheck::TyEnv;
-use crate::semantics::Value;
+use crate::semantics::{NameEnv, NzEnv, TyEnv, Value};
use crate::syntax::{ExprKind, Span, V};
pub(crate) type Type = Value;
diff --git a/dhall/src/semantics/tck/typecheck.rs b/dhall/src/semantics/tck/typecheck.rs
index 7a225f7..789105f 100644
--- a/dhall/src/semantics/tck/typecheck.rs
+++ b/dhall/src/semantics/tck/typecheck.rs
@@ -3,71 +3,19 @@ use std::cmp::max;
use std::collections::HashMap;
use crate::error::{TypeError, TypeMessage};
-use crate::semantics::nze::{NameEnv, NzVar, VarEnv};
-use crate::semantics::phase::normalize::{merge_maps, NzEnv};
+use crate::semantics::phase::normalize::merge_maps;
use crate::semantics::phase::typecheck::{
builtin_to_value, const_to_value, type_of_builtin,
};
use crate::semantics::phase::Normalized;
use crate::semantics::{
- Binder, Closure, TyExpr, TyExprKind, Type, Value, ValueKind,
+ Binder, Closure, NzVar, TyEnv, TyExpr, TyExprKind, Type, Value, ValueKind,
};
use crate::syntax;
use crate::syntax::{
- BinOp, Builtin, Const, Expr, ExprKind, InterpolatedTextContents, Label,
- Span, V,
+ BinOp, Builtin, Const, Expr, ExprKind, InterpolatedTextContents, Span,
};
-#[derive(Debug, Clone)]
-pub(crate) struct TyEnv {
- names: NameEnv,
- items: NzEnv,
-}
-
-impl TyEnv {
- pub fn new() -> Self {
- TyEnv {
- names: NameEnv::new(),
- items: NzEnv::new(),
- }
- }
- pub fn from_nzenv_alpha(items: &NzEnv) -> Self {
- TyEnv {
- names: NameEnv::from_binders(
- std::iter::repeat("_".into()).take(items.size()),
- ),
- items: items.clone(),
- }
- }
- pub fn as_varenv(&self) -> VarEnv {
- self.names.as_varenv()
- }
- pub fn as_nzenv(&self) -> &NzEnv {
- &self.items
- }
- pub fn as_nameenv(&self) -> &NameEnv {
- &self.names
- }
-
- pub fn insert_type(&self, x: &Label, t: Type) -> Self {
- TyEnv {
- names: self.names.insert(x),
- items: self.items.insert_type(t),
- }
- }
- pub fn insert_value(&self, x: &Label, e: Value) -> Self {
- TyEnv {
- names: self.names.insert(x),
- items: self.items.insert_value(e),
- }
- }
- pub fn lookup(&self, var: &V<Label>) -> Option<(TyExprKind, Type)> {
- let var = self.names.unlabel_var(var)?;
- let ty = self.items.lookup_val(&var).get_type().unwrap();
- Some((TyExprKind::Var(var), ty))
- }
-}
-
fn type_of_recordtype<'a>(
tys: impl Iterator<Item = Cow<'a, TyExpr>>,
) -> Result<Type, TypeError> {