Stop tracking the absence of Embed values at the type level

3 files changed, 17 insertions, 19 deletions

diff --git a/dhall/src/phase/mod.rs b/dhall/src/phase/mod.rs
index 8c93889..7364949 100644
--- a/dhall/src/phase/mod.rs
+++ b/dhall/src/phase/mod.rs
@@ -2,7 +2,7 @@ use std::borrow::Cow;
 use std::fmt::Display;
 use std::path::Path;
 
-use dhall_syntax::{Const, Import, SubExpr, X};
+use dhall_syntax::{Const, Import, SubExpr};
 
 use crate::core::thunk::{Thunk, TypedThunk};
 use crate::core::value::Value;
@@ -20,7 +20,7 @@ pub(crate) mod typecheck;
 pub type ParsedSubExpr = SubExpr<Import>;
 pub type DecodedSubExpr = SubExpr<Import>;
 pub type ResolvedSubExpr = SubExpr<Normalized>;
-pub type NormalizedSubExpr = SubExpr<X>;
+pub type NormalizedSubExpr = SubExpr<Normalized>;
 
 #[derive(Debug, Clone)]
 pub struct Parsed(ParsedSubExpr, ImportRoot);
diff --git a/dhall/src/phase/normalize.rs b/dhall/src/phase/normalize.rs
index 644f98c..f1045a5 100644
--- a/dhall/src/phase/normalize.rs
+++ b/dhall/src/phase/normalize.rs
@@ -2,14 +2,14 @@ use std::collections::HashMap;
 
 use dhall_syntax::{
     BinOp, Builtin, ExprF, InterpolatedText, InterpolatedTextContents,
-    NaiveDouble, X,
+    NaiveDouble,
 };
 
 use crate::core::context::NormalizationContext;
 use crate::core::thunk::{Thunk, TypedThunk};
 use crate::core::value::Value;
 use crate::core::var::Subst;
-use crate::phase::{NormalizedSubExpr, ResolvedSubExpr, Typed};
+use crate::phase::{Normalized, NormalizedSubExpr, ResolvedSubExpr, Typed};
 
 pub type InputSubExpr = ResolvedSubExpr;
 pub type OutputSubExpr = NormalizedSubExpr;
@@ -86,7 +86,7 @@ pub fn apply_builtin(b: Builtin, args: Vec<Thunk>) -> Value {
                     // Empty string literal.
                     [] => {
                         // Printing InterpolatedText takes care of all the escaping
-                        let txt: InterpolatedText<X> =
+                        let txt: InterpolatedText<Normalized> =
                             std::iter::empty().collect();
                         let s = txt.to_string();
                         Ok((
@@ -98,10 +98,11 @@ pub fn apply_builtin(b: Builtin, args: Vec<Thunk>) -> Value {
                     // interpolations, there is a single Text item) in the literal.
                     [InterpolatedTextContents::Text(s)] => {
                         // Printing InterpolatedText takes care of all the escaping
-                        let txt: InterpolatedText<X> = std::iter::once(
-                            InterpolatedTextContents::Text(s.clone()),
-                        )
-                        .collect();
+                        let txt: InterpolatedText<Normalized> =
+                            std::iter::once(InterpolatedTextContents::Text(
+                                s.clone(),
+                            ))
+                            .collect();
                         let s = txt.to_string();
                         Ok((
                             r,
@@ -376,7 +377,7 @@ pub fn normalize_whnf(ctx: NormalizationContext, expr: InputSubExpr) -> Value {
     }
 
     // Thunk subexpressions
-    let expr: ExprF<Thunk, X> =
+    let expr: ExprF<Thunk, Normalized> =
         expr.as_ref().map_ref_with_special_handling_of_binders(
             |e| Thunk::new(ctx.clone(), e.clone()),
             |x, e| Thunk::new(ctx.skip(x), e.clone()),
@@ -391,7 +392,7 @@ enum Ret<'a> {
     Value(Value),
     Thunk(Thunk),
     ThunkRef(&'a Thunk),
-    Expr(ExprF<Thunk, X>),
+    Expr(ExprF<Thunk, Normalized>),
 }
 
 /// Performs an intersection of two HashMaps.
@@ -636,7 +637,7 @@ fn apply_binop<'a>(o: BinOp, x: &'a Thunk, y: &'a Thunk) -> Option<Ret<'a>> {
     })
 }
 
-pub fn normalize_one_layer(expr: ExprF<Thunk, X>) -> Value {
+pub fn normalize_one_layer(expr: ExprF<Thunk, Normalized>) -> Value {
     use Value::{
         AppliedBuiltin, BoolLit, DoubleLit, EmptyListLit, IntegerLit, Lam,
         NEListLit, NEOptionalLit, NaturalLit, Pi, RecordLit, RecordType,
diff --git a/dhall/src/phase/typecheck.rs b/dhall/src/phase/typecheck.rs
index ecf9793..96ff246 100644
--- a/dhall/src/phase/typecheck.rs
+++ b/dhall/src/phase/typecheck.rs
@@ -2,7 +2,6 @@ use std::collections::HashMap;
 
 use dhall_syntax::{
     rc, Builtin, Const, Expr, ExprF, InterpolatedTextContents, Label, SubExpr,
-    X,
 };
 
 use crate::core::context::{NormalizationContext, TypecheckContext};
@@ -214,7 +213,7 @@ macro_rules! make_type {
     };
 }
 
-fn type_of_builtin(b: Builtin) -> Expr<X> {
+fn type_of_builtin<E>(b: Builtin) -> Expr<E> {
     use dhall_syntax::Builtin::*;
     match b {
         Bool | Natural | Integer | Double | Text => make_type!(Type),
@@ -398,7 +397,7 @@ fn type_with(
 /// layer.
 fn type_last_layer(
     ctx: &TypecheckContext,
-    e: &ExprF<Typed, X>,
+    e: &ExprF<Typed, Normalized>,
 ) -> Result<Ret, TypeError> {
     use crate::error::TypeMessage::*;
     use dhall_syntax::BinOp::*;
@@ -598,9 +597,7 @@ fn type_last_layer(
             }
         }
         Const(c) => Ok(RetWhole(Typed::from_const(*c))),
-        Builtin(b) => {
-            Ok(RetTypeOnly(mktype(ctx, rc(type_of_builtin(*b)).absurd())?))
-        }
+        Builtin(b) => Ok(RetTypeOnly(mktype(ctx, rc(type_of_builtin(*b)))?)),
         BoolLit(_) => Ok(RetTypeOnly(builtin_to_type(Bool)?)),
         NaturalLit(_) => Ok(RetTypeOnly(builtin_to_type(Natural)?)),
         IntegerLit(_) => Ok(RetTypeOnly(builtin_to_type(Integer)?)),
@@ -1016,7 +1013,7 @@ pub fn typecheck(e: Resolved) -> Result<Typed, TypeError> {
 
 pub fn typecheck_with(e: Resolved, ty: &Type) -> Result<Typed, TypeError> {
     let expr: SubExpr<_> = e.0;
-    let ty: SubExpr<_> = ty.to_expr().absurd();
+    let ty: SubExpr<_> = ty.to_expr();
     type_of(expr.rewrap(ExprF::Annot(expr.clone(), ty)))
 }
 pub fn skip_typecheck(e: Resolved) -> Typed {