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-rw-r--r--dhall/src/phase/mod.rs16
-rw-r--r--dhall/src/phase/normalize.rs90
-rw-r--r--dhall/src/phase/typecheck.rs177
3 files changed, 117 insertions, 166 deletions
diff --git a/dhall/src/phase/mod.rs b/dhall/src/phase/mod.rs
index e58e689..91d64c3 100644
--- a/dhall/src/phase/mod.rs
+++ b/dhall/src/phase/mod.rs
@@ -4,7 +4,7 @@ use std::path::Path;
use dhall_syntax::{Const, SubExpr};
-use crate::core::value::{TypedValue, Value};
+use crate::core::value::Value;
use crate::core::valuef::ValueF;
use crate::core::var::{AlphaVar, Shift, Subst};
use crate::error::{EncodeError, Error, ImportError, TypeError};
@@ -33,7 +33,7 @@ pub struct Resolved(ResolvedSubExpr);
/// A typed expression
#[derive(Debug, Clone)]
-pub struct Typed(TypedValue);
+pub struct Typed(Value);
/// A normalized expression.
///
@@ -91,12 +91,12 @@ impl Typed {
}
pub(crate) fn from_const(c: Const) -> Self {
- Typed(TypedValue::from_const(c))
+ Typed(Value::from_const(c))
}
pub fn from_valuef_and_type(v: ValueF, t: Typed) -> Self {
- Typed(TypedValue::from_valuef_and_type(v, t.into_typedvalue()))
+ Typed(Value::from_valuef_and_type(v, t.into_value()))
}
- pub(crate) fn from_typedvalue(th: TypedValue) -> Self {
+ pub(crate) fn from_value(th: Value) -> Self {
Typed(th)
}
pub fn const_type() -> Self {
@@ -112,7 +112,7 @@ impl Typed {
pub fn to_value(&self) -> Value {
self.0.to_value()
}
- pub(crate) fn into_typedvalue(self) -> TypedValue {
+ pub(crate) fn into_value(self) -> Value {
self.0
}
@@ -155,8 +155,8 @@ impl Shift for Normalized {
}
}
-impl Subst<TypedValue> for Typed {
- fn subst_shift(&self, var: &AlphaVar, val: &TypedValue) -> Self {
+impl Subst<Value> for Typed {
+ fn subst_shift(&self, var: &AlphaVar, val: &Value) -> Self {
Typed(self.0.subst_shift(var, val))
}
}
diff --git a/dhall/src/phase/normalize.rs b/dhall/src/phase/normalize.rs
index 27858d8..821c5fd 100644
--- a/dhall/src/phase/normalize.rs
+++ b/dhall/src/phase/normalize.rs
@@ -5,7 +5,7 @@ use dhall_syntax::{
NaiveDouble,
};
-use crate::core::value::{TypedValue, Value};
+use crate::core::value::Value;
use crate::core::valuef::ValueF;
use crate::core::var::{Shift, Subst};
use crate::phase::{Normalized, NormalizedSubExpr};
@@ -26,9 +26,7 @@ macro_rules! make_closure {
(λ($var:ident : $($ty:tt)*) -> $($rest:tt)*) => {
ValueF::Lam(
Label::from(stringify!($var)).into(),
- TypedValue::from_value_simple_type(
- make_closure!($($ty)*),
- ),
+ make_closure!($($ty)*),
make_closure!($($rest)*),
).into_value_untyped()
};
@@ -51,10 +49,10 @@ macro_rules! make_closure {
make_closure!($($rest)*),
Value::from_valuef_and_type(
ValueF::NaturalLit(1),
- TypedValue::from_value(make_closure!(Natural))
+ make_closure!(Natural)
),
)).into_value_with_type(
- TypedValue::from_value(make_closure!(Natural))
+ make_closure!(Natural)
)
};
([ $($head:tt)* ] # $($tail:tt)*) => {
@@ -74,10 +72,7 @@ pub(crate) fn apply_builtin(b: Builtin, args: Vec<Value>) -> ValueF {
// Return Ok((unconsumed args, returned value)), or Err(()) if value could not be produced.
let ret = match (b, args.as_slice()) {
- (OptionalNone, [t, r..]) => Ok((
- r,
- EmptyOptionalLit(TypedValue::from_value_simple_type(t.clone())),
- )),
+ (OptionalNone, [t, r..]) => Ok((r, EmptyOptionalLit(t.clone()))),
(NaturalIsZero, [n, r..]) => match &*n.as_whnf() {
NaturalLit(n) => Ok((r, BoolLit(*n == 0))),
_ => Err(()),
@@ -199,16 +194,12 @@ pub(crate) fn apply_builtin(b: Builtin, args: Vec<Value>) -> ValueF {
let mut kts = HashMap::new();
kts.insert(
"index".into(),
- TypedValue::from_valuef_untyped(ValueF::from_builtin(
- Natural,
- )),
+ Value::from_valuef_untyped(ValueF::from_builtin(Natural)),
);
kts.insert("value".into(), t.clone());
Ok((
r,
- EmptyListLit(TypedValue::from_valuef_untyped(RecordType(
- kts,
- ))),
+ EmptyListLit(Value::from_valuef_untyped(RecordType(kts))),
))
}
NEListLit(xs) => {
@@ -252,9 +243,7 @@ pub(crate) fn apply_builtin(b: Builtin, args: Vec<Value>) -> ValueF {
[ var(x, 1) ] # var(xs, 0)
)
})
- .app_valuef(EmptyListLit(
- TypedValue::from_value_simple_type(t.clone()),
- )),
+ .app_valuef(EmptyListLit(t.clone())),
)),
},
(ListFold, [_, l, _, cons, nil, r..]) => match &*l.as_whnf() {
@@ -288,9 +277,7 @@ pub(crate) fn apply_builtin(b: Builtin, args: Vec<Value>) -> ValueF {
ValueF::from_builtin(Optional).app_value(t.clone()),
)
.app_value(make_closure!(λ(x: #t) -> Some(var(x, 0))))
- .app_valuef(EmptyOptionalLit(
- TypedValue::from_value_simple_type(t.clone()),
- )),
+ .app_valuef(EmptyOptionalLit(t.clone())),
)),
},
(OptionalFold, [_, v, _, just, nothing, r..]) => match &*v.as_whnf() {
@@ -346,10 +333,7 @@ pub(crate) fn apply_any(f: Value, a: Value) -> ValueF {
let f_borrow = f.as_whnf();
match &*f_borrow {
- ValueF::Lam(x, _, e) => {
- let val = TypedValue::from_value(a);
- e.subst_shift(&x.into(), &val).to_whnf()
- }
+ ValueF::Lam(x, _, e) => e.subst_shift(&x.into(), &a).to_whnf(),
ValueF::AppliedBuiltin(b, args) => {
use std::iter::once;
let args = args.iter().cloned().chain(once(a.clone())).collect();
@@ -639,21 +623,18 @@ fn apply_binop<'a>(o: BinOp, x: &'a Value, y: &'a Value) -> Option<Ret<'a>> {
}
(RecursiveRecordTypeMerge, RecordType(kvs1), RecordType(kvs2)) => {
let kvs = merge_maps(kvs1, kvs2, |v1, v2| {
- TypedValue::from_valuef_untyped(ValueF::PartialExpr(
- ExprF::BinOp(
- RecursiveRecordTypeMerge,
- v1.to_value(),
- v2.to_value(),
- ),
- ))
+ Value::from_valuef_untyped(ValueF::PartialExpr(ExprF::BinOp(
+ RecursiveRecordTypeMerge,
+ v1.to_value(),
+ v2.to_value(),
+ )))
});
Ret::ValueF(RecordType(kvs))
}
- (Equivalence, _, _) => Ret::ValueF(ValueF::Equivalence(
- TypedValue::from_value_simple_type(x.clone()),
- TypedValue::from_value_simple_type(y.clone()),
- )),
+ (Equivalence, _, _) => {
+ Ret::ValueF(ValueF::Equivalence(x.clone(), y.clone()))
+ }
_ => return None,
})
@@ -674,18 +655,9 @@ pub(crate) fn normalize_one_layer(expr: ExprF<Value, Normalized>) -> ValueF {
ExprF::Var(_) => unreachable!(),
ExprF::Annot(x, _) => Ret::Value(x),
ExprF::Assert(_) => Ret::Expr(expr),
- ExprF::Lam(x, t, e) => {
- Ret::ValueF(Lam(x.into(), TypedValue::from_value(t), e))
- }
- ExprF::Pi(x, t, e) => Ret::ValueF(Pi(
- x.into(),
- TypedValue::from_value(t),
- TypedValue::from_value(e),
- )),
- ExprF::Let(x, _, v, b) => {
- let v = TypedValue::from_value(v);
- Ret::Value(b.subst_shift(&x.into(), &v))
- }
+ ExprF::Lam(x, t, e) => Ret::ValueF(Lam(x.into(), t, e)),
+ ExprF::Pi(x, t, e) => Ret::ValueF(Pi(x.into(), t, e)),
+ ExprF::Let(x, _, v, b) => Ret::Value(b.subst_shift(&x.into(), &v)),
ExprF::App(v, a) => Ret::ValueF(v.app_value(a)),
ExprF::Builtin(b) => Ret::ValueF(ValueF::from_builtin(b)),
ExprF::Const(c) => Ret::ValueF(ValueF::Const(c)),
@@ -699,9 +671,7 @@ pub(crate) fn normalize_one_layer(expr: ExprF<Value, Normalized>) -> ValueF {
let t_borrow = t.as_whnf();
match &*t_borrow {
AppliedBuiltin(Builtin::List, args) if args.len() == 1 => {
- Ret::ValueF(EmptyListLit(
- TypedValue::from_value_simple_type(args[0].clone()),
- ))
+ Ret::ValueF(EmptyListLit(args[0].clone()))
}
_ => {
drop(t_borrow);
@@ -715,16 +685,12 @@ pub(crate) fn normalize_one_layer(expr: ExprF<Value, Normalized>) -> ValueF {
ExprF::RecordLit(kvs) => {
Ret::ValueF(RecordLit(kvs.into_iter().collect()))
}
- ExprF::RecordType(kts) => Ret::ValueF(RecordType(
- kts.into_iter()
- .map(|(k, t)| (k, TypedValue::from_value(t)))
- .collect(),
- )),
- ExprF::UnionType(kts) => Ret::ValueF(UnionType(
- kts.into_iter()
- .map(|(k, t)| (k, t.map(|t| TypedValue::from_value(t))))
- .collect(),
- )),
+ ExprF::RecordType(kts) => {
+ Ret::ValueF(RecordType(kts.into_iter().collect()))
+ }
+ ExprF::UnionType(kts) => {
+ Ret::ValueF(UnionType(kts.into_iter().collect()))
+ }
ExprF::TextLit(elts) => {
use InterpolatedTextContents::Expr;
let elts: Vec<_> = squash_textlit(elts.into_iter());
diff --git a/dhall/src/phase/typecheck.rs b/dhall/src/phase/typecheck.rs
index e24f5a3..e65881e 100644
--- a/dhall/src/phase/typecheck.rs
+++ b/dhall/src/phase/typecheck.rs
@@ -5,7 +5,7 @@ use dhall_syntax::{
};
use crate::core::context::TypecheckContext;
-use crate::core::value::TypedValue;
+use crate::core::value::Value;
use crate::core::valuef::ValueF;
use crate::core::var::{Shift, Subst};
use crate::error::{TypeError, TypeMessage};
@@ -14,9 +14,9 @@ use crate::phase::Normalized;
fn tck_pi_type(
ctx: &TypecheckContext,
x: Label,
- tx: TypedValue,
- te: TypedValue,
-) -> Result<TypedValue, TypeError> {
+ tx: Value,
+ te: Value,
+) -> Result<Value, TypeError> {
use crate::error::TypeMessage::*;
let ctx2 = ctx.insert_type(&x, tx.clone());
@@ -37,16 +37,16 @@ fn tck_pi_type(
let k = function_check(ka, kb);
- Ok(TypedValue::from_valuef_and_type(
+ Ok(Value::from_valuef_and_type(
ValueF::Pi(x.into(), tx, te),
- TypedValue::from_const(k),
+ Value::from_const(k),
))
}
fn tck_record_type(
ctx: &TypecheckContext,
- kts: impl IntoIterator<Item = Result<(Label, TypedValue), TypeError>>,
-) -> Result<TypedValue, TypeError> {
+ kts: impl IntoIterator<Item = Result<(Label, Value), TypeError>>,
+) -> Result<Value, TypeError> {
use crate::error::TypeMessage::*;
use std::collections::hash_map::Entry;
let mut new_kts = HashMap::new();
@@ -70,18 +70,18 @@ fn tck_record_type(
// An empty record type has type Type
let k = k.unwrap_or(Const::Type);
- Ok(TypedValue::from_valuef_and_type(
+ Ok(Value::from_valuef_and_type(
ValueF::RecordType(new_kts),
- TypedValue::from_const(k),
+ Value::from_const(k),
))
}
fn tck_union_type<Iter>(
ctx: &TypecheckContext,
kts: Iter,
-) -> Result<TypedValue, TypeError>
+) -> Result<Value, TypeError>
where
- Iter: IntoIterator<Item = Result<(Label, Option<TypedValue>), TypeError>>,
+ Iter: IntoIterator<Item = Result<(Label, Option<Value>), TypeError>>,
{
use crate::error::TypeMessage::*;
use std::collections::hash_map::Entry;
@@ -115,9 +115,9 @@ where
// an union type with only unary variants also has type Type
let k = k.unwrap_or(Const::Type);
- Ok(TypedValue::from_valuef_and_type(
+ Ok(Value::from_valuef_and_type(
ValueF::UnionType(new_kts),
- TypedValue::from_const(k),
+ Value::from_const(k),
))
}
@@ -130,10 +130,10 @@ fn function_check(a: Const, b: Const) -> Const {
}
}
-pub(crate) fn type_of_const(c: Const) -> Result<TypedValue, TypeError> {
+pub(crate) fn type_of_const(c: Const) -> Result<Value, TypeError> {
match c {
- Const::Type => Ok(TypedValue::from_const(Const::Kind)),
- Const::Kind => Ok(TypedValue::from_const(Const::Sort)),
+ Const::Type => Ok(Value::from_const(Const::Kind)),
+ Const::Kind => Ok(Value::from_const(Const::Sort)),
Const::Sort => {
Err(TypeError::new(&TypecheckContext::new(), TypeMessage::Sort))
}
@@ -282,16 +282,16 @@ fn type_of_builtin<E>(b: Builtin) -> Expr<E> {
}
// TODO: this can't fail in practise
-pub(crate) fn builtin_to_type(b: Builtin) -> Result<TypedValue, TypeError> {
+pub(crate) fn builtin_to_type(b: Builtin) -> Result<Value, TypeError> {
type_with(&TypecheckContext::new(), SubExpr::from_builtin(b))
}
/// Intermediary return type
enum Ret {
/// Returns the contained value as is
- RetWhole(TypedValue),
- /// Use the contained TypedValue as the type of the input expression
- RetTypeOnly(TypedValue),
+ RetWhole(Value),
+ /// Use the contained Value as the type of the input expression
+ RetTypeOnly(Value),
}
/// Type-check an expression and return the expression alongside its type if type-checking
@@ -301,7 +301,7 @@ enum Ret {
fn type_with(
ctx: &TypecheckContext,
e: SubExpr<Normalized>,
-) -> Result<TypedValue, TypeError> {
+) -> Result<Value, TypeError> {
use dhall_syntax::ExprF::{Annot, Embed, Lam, Let, Pi, Var};
use Ret::*;
@@ -313,7 +313,7 @@ fn type_with(
let v = ValueF::Lam(x.clone().into(), tx.clone(), b.to_value());
let tb = b.get_type()?.into_owned();
let t = tck_pi_type(ctx, x.clone(), tx, tb)?;
- TypedValue::from_valuef_and_type(v, t)
+ Value::from_valuef_and_type(v, t)
}
Pi(x, ta, tb) => {
let ta = type_with(ctx, ta.clone())?;
@@ -331,7 +331,7 @@ fn type_with(
let v = type_with(ctx, v)?;
return type_with(&ctx.insert_value(x, v.clone())?, e.clone());
}
- Embed(p) => p.clone().into_typed().into_typedvalue(),
+ Embed(p) => p.clone().into_typed().into_value(),
Var(var) => match ctx.lookup(&var) {
Some(typed) => typed.clone(),
None => {
@@ -352,10 +352,7 @@ fn type_with(
match ret {
RetTypeOnly(typ) => {
let expr = expr.map_ref(|typed| typed.to_value());
- TypedValue::from_valuef_and_type(
- ValueF::PartialExpr(expr),
- typ,
- )
+ Value::from_valuef_and_type(ValueF::PartialExpr(expr), typ)
}
RetWhole(tt) => tt,
}
@@ -367,7 +364,7 @@ fn type_with(
/// layer.
fn type_last_layer(
ctx: &TypecheckContext,
- e: &ExprF<TypedValue, Normalized>,
+ e: &ExprF<Value, Normalized>,
) -> Result<Ret, TypeError> {
use crate::error::TypeMessage::*;
use dhall_syntax::BinOp::*;
@@ -466,10 +463,10 @@ fn type_last_layer(
));
}
- Ok(RetTypeOnly(TypedValue::from_valuef_and_type(
+ Ok(RetTypeOnly(Value::from_valuef_and_type(
ValueF::from_builtin(dhall_syntax::Builtin::List)
.app_value(t.to_value()),
- TypedValue::from_const(Type),
+ Value::from_const(Type),
)))
}
SomeLit(x) => {
@@ -478,10 +475,10 @@ fn type_last_layer(
return Err(TypeError::new(ctx, InvalidOptionalType(t)));
}
- Ok(RetTypeOnly(TypedValue::from_valuef_and_type(
+ Ok(RetTypeOnly(Value::from_valuef_and_type(
ValueF::from_builtin(dhall_syntax::Builtin::Optional)
.app_value(t.to_value()),
- TypedValue::from_const(Type),
+ Value::from_const(Type),
)))
}
RecordType(kts) => Ok(RetWhole(tck_record_type(
@@ -545,7 +542,7 @@ fn type_last_layer(
// ))),
}
}
- Const(c) => Ok(RetWhole(TypedValue::from_const(*c))),
+ Const(c) => Ok(RetWhole(Value::from_const(*c))),
Builtin(b) => Ok(RetTypeOnly(type_with(ctx, rc(type_of_builtin(*b)))?)),
BoolLit(_) => Ok(RetTypeOnly(builtin_to_type(Bool)?)),
NaturalLit(_) => Ok(RetTypeOnly(builtin_to_type(Natural)?)),
@@ -607,43 +604,38 @@ fn type_last_layer(
// records of records when merging.
fn combine_record_types(
ctx: &TypecheckContext,
- kts_l: &HashMap<Label, TypedValue>,
- kts_r: &HashMap<Label, TypedValue>,
- ) -> Result<TypedValue, TypeError> {
+ kts_l: &HashMap<Label, Value>,
+ kts_r: &HashMap<Label, Value>,
+ ) -> Result<Value, TypeError> {
use crate::phase::normalize::outer_join;
// If the Label exists for both records and the values
// are records themselves, then we hit the recursive case.
// Otherwise we have a field collision.
- let combine =
- |k: &Label,
- inner_l: &TypedValue,
- inner_r: &TypedValue|
- -> Result<TypedValue, TypeError> {
- match (&*inner_l.as_whnf(), &*inner_r.as_whnf()) {
- (
- ValueF::RecordType(inner_l_kvs),
- ValueF::RecordType(inner_r_kvs),
- ) => combine_record_types(
- ctx,
- inner_l_kvs,
- inner_r_kvs,
- ),
- (_, _) => Err(TypeError::new(
- ctx,
- FieldCollision(k.clone()),
- )),
+ let combine = |k: &Label,
+ inner_l: &Value,
+ inner_r: &Value|
+ -> Result<Value, TypeError> {
+ match (&*inner_l.as_whnf(), &*inner_r.as_whnf()) {
+ (
+ ValueF::RecordType(inner_l_kvs),
+ ValueF::RecordType(inner_r_kvs),
+ ) => {
+ combine_record_types(ctx, inner_l_kvs, inner_r_kvs)
}
- };
+ (_, _) => {
+ Err(TypeError::new(ctx, FieldCollision(k.clone())))
+ }
+ }
+ };
- let kts: HashMap<Label, Result<TypedValue, TypeError>> =
- outer_join(
- |l| Ok(l.clone()),
- |r| Ok(r.clone()),
- combine,
- kts_l,
- kts_r,
- );
+ let kts: HashMap<Label, Result<Value, TypeError>> = outer_join(
+ |l| Ok(l.clone()),
+ |r| Ok(r.clone()),
+ combine,
+ kts_l,
+ kts_r,
+ );
Ok(tck_record_type(
ctx,
@@ -684,35 +676,30 @@ fn type_last_layer(
// records of records when merging.
fn combine_record_types(
ctx: &TypecheckContext,
- kts_l: &HashMap<Label, TypedValue>,
- kts_r: &HashMap<Label, TypedValue>,
- ) -> Result<TypedValue, TypeError> {
+ kts_l: &HashMap<Label, Value>,
+ kts_r: &HashMap<Label, Value>,
+ ) -> Result<Value, TypeError> {
use crate::phase::normalize::intersection_with_key;
// If the Label exists for both records and the values
// are records themselves, then we hit the recursive case.
// Otherwise we have a field collision.
- let combine =
- |k: &Label,
- kts_l_inner: &TypedValue,
- kts_r_inner: &TypedValue|
- -> Result<TypedValue, TypeError> {
- match (&*kts_l_inner.as_whnf(), &*kts_r_inner.as_whnf())
- {
- (
- ValueF::RecordType(kvs_l_inner),
- ValueF::RecordType(kvs_r_inner),
- ) => combine_record_types(
- ctx,
- kvs_l_inner,
- kvs_r_inner,
- ),
- (_, _) => Err(TypeError::new(
- ctx,
- FieldCollision(k.clone()),
- )),
+ let combine = |k: &Label,
+ kts_l_inner: &Value,
+ kts_r_inner: &Value|
+ -> Result<Value, TypeError> {
+ match (&*kts_l_inner.as_whnf(), &*kts_r_inner.as_whnf()) {
+ (
+ ValueF::RecordType(kvs_l_inner),
+ ValueF::RecordType(kvs_r_inner),
+ ) => {
+ combine_record_types(ctx, kvs_l_inner, kvs_r_inner)
}
- };
+ (_, _) => {
+ Err(TypeError::new(ctx, FieldCollision(k.clone())))
+ }
+ }
+ };
let kts = intersection_with_key(combine, kts_l, kts_r);
@@ -747,8 +734,8 @@ fn type_last_layer(
k_l
} else {
return Err(mkerr(RecordTypeMismatch(
- TypedValue::from_const(k_l),
- TypedValue::from_const(k_r),
+ Value::from_const(k_l),
+ Value::from_const(k_r),
l.clone(),
r.clone(),
)));
@@ -779,7 +766,7 @@ fn type_last_layer(
// Ensure that the records combine without a type error
// and if not output the final Const value.
combine_record_types(ctx, kts_x, kts_y)
- .and(Ok(RetTypeOnly(TypedValue::from_const(k))))
+ .and(Ok(RetTypeOnly(Value::from_const(k))))
}
BinOp(o @ ListAppend, l, r) => {
match &*l.get_type()?.as_whnf() {
@@ -814,7 +801,7 @@ fn type_last_layer(
)));
}
- Ok(RetTypeOnly(TypedValue::from_const(Type)))
+ Ok(RetTypeOnly(Value::from_const(Type)))
}
BinOp(o, l, r) => {
let t = builtin_to_type(match o {
@@ -941,7 +928,7 @@ fn type_last_layer(
};
}
- Ok(RetTypeOnly(TypedValue::from_valuef_and_type(
+ Ok(RetTypeOnly(Value::from_valuef_and_type(
ValueF::RecordType(new_kts),
record_type.get_type()?.into_owned(),
)))
@@ -952,15 +939,13 @@ fn type_last_layer(
/// `type_of` is the same as `type_with` with an empty context, meaning that the
/// expression must be closed (i.e. no free variables), otherwise type-checking
/// will fail.
-pub(crate) fn typecheck(
- e: SubExpr<Normalized>,
-) -> Result<TypedValue, TypeError> {
+pub(crate) fn typecheck(e: SubExpr<Normalized>) -> Result<Value, TypeError> {
type_with(&TypecheckContext::new(), e)
}
pub(crate) fn typecheck_with(
expr: SubExpr<Normalized>,
ty: SubExpr<Normalized>,
-) -> Result<TypedValue, TypeError> {
+) -> Result<Value, TypeError> {
typecheck(expr.rewrap(ExprF::Annot(expr.clone(), ty)))
}