Remove old-style optional literals

9 files changed, 19 insertions, 70 deletions

diff --git a/dhall-lang b/dhall-lang
-Subproject b1f98152c404b661233db9a834d8e31ab270447
+Subproject b1992297d702c67d2e1b1597af5c533af293430
diff --git a/dhall/src/phase/binary.rs b/dhall/src/phase/binary.rs
index 874b4fb..dcf60bb 100644
--- a/dhall/src/phase/binary.rs
+++ b/dhall/src/phase/binary.rs
@@ -115,18 +115,22 @@ fn cbor_value_to_dhall(
                     .collect::<Result<Vec<_>, _>>()?;
                 NEListLit(rest)
             }
-            [U64(5), t] => {
-                let t = cbor_value_to_dhall(&t)?;
-                OldOptionalLit(None, t)
-            }
             [U64(5), Null, x] => {
                 let x = cbor_value_to_dhall(&x)?;
                 SomeLit(x)
             }
+            // Old-style optional literals
+            [U64(5), t] => {
+                let t = cbor_value_to_dhall(&t)?;
+                App(rc(ExprF::Builtin(Builtin::OptionalNone)), t)
+            }
             [U64(5), t, x] => {
                 let x = cbor_value_to_dhall(&x)?;
                 let t = cbor_value_to_dhall(&t)?;
-                OldOptionalLit(Some(x), t)
+                Annot(
+                    rc(SomeLit(x)),
+                    rc(App(rc(ExprF::Builtin(Builtin::Optional)), t)),
+                )
             }
             [U64(6), x, y] => {
                 let x = cbor_value_to_dhall(&x)?;
@@ -460,8 +464,6 @@ where
             )
         }
         Annot(x, y) => ser_seq!(ser; tag(26), expr(x), expr(y)),
-        OldOptionalLit(None, t) => ser_seq!(ser; tag(5), expr(t)),
-        OldOptionalLit(Some(x), t) => ser_seq!(ser; tag(5), expr(t), expr(x)),
         SomeLit(x) => ser_seq!(ser; tag(5), null(), expr(x)),
         EmptyListLit(x) => ser_seq!(ser; tag(4), expr(x)),
         NEListLit(xs) => ser.collect_seq(
diff --git a/dhall/src/phase/normalize.rs b/dhall/src/phase/normalize.rs
index 35d32cb..f3684d1 100644
--- a/dhall/src/phase/normalize.rs
+++ b/dhall/src/phase/normalize.rs
@@ -611,9 +611,9 @@ 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 {
     use Value::{
-        BoolLit, DoubleLit, EmptyListLit, EmptyOptionalLit, IntegerLit, Lam,
-        NEListLit, NEOptionalLit, NaturalLit, Pi, RecordLit, RecordType,
-        TextLit, UnionConstructor, UnionLit, UnionType,
+        BoolLit, DoubleLit, EmptyListLit, IntegerLit, Lam, NEListLit,
+        NEOptionalLit, NaturalLit, Pi, RecordLit, RecordType, TextLit,
+        UnionConstructor, UnionLit, UnionType,
     };
 
     let ret = match expr {
@@ -639,10 +639,6 @@ pub fn normalize_one_layer(expr: ExprF<Thunk, X>) -> Value {
         ExprF::NaturalLit(n) => Ret::Value(NaturalLit(n)),
         ExprF::IntegerLit(n) => Ret::Value(IntegerLit(n)),
         ExprF::DoubleLit(n) => Ret::Value(DoubleLit(n)),
-        ExprF::OldOptionalLit(None, t) => {
-            Ret::Value(EmptyOptionalLit(TypeThunk::from_thunk(t)))
-        }
-        ExprF::OldOptionalLit(Some(e), _) => Ret::Value(NEOptionalLit(e)),
         ExprF::SomeLit(e) => Ret::Value(NEOptionalLit(e)),
         ExprF::EmptyListLit(t) => {
             Ret::Value(EmptyListLit(TypeThunk::from_thunk(t)))
diff --git a/dhall/src/phase/typecheck.rs b/dhall/src/phase/typecheck.rs
index efdc2bb..8551503 100644
--- a/dhall/src/phase/typecheck.rs
+++ b/dhall/src/phase/typecheck.rs
@@ -329,9 +329,7 @@ fn type_with(
     ctx: &TypecheckContext,
     e: SubExpr<Span, Normalized>,
 ) -> Result<Typed, TypeError> {
-    use dhall_syntax::ExprF::{
-        Annot, App, Embed, Lam, Let, OldOptionalLit, Pi, SomeLit, Var,
-    };
+    use dhall_syntax::ExprF::{Annot, Embed, Lam, Let, Pi, Var};
 
     use Ret::*;
     Ok(match e.as_ref() {
@@ -364,18 +362,6 @@ fn type_with(
             let v = type_with(ctx, v)?;
             return type_with(&ctx.insert_value(x, v.clone())?, e.clone());
         }
-        OldOptionalLit(None, t) => {
-            let none = SubExpr::from_builtin(Builtin::OptionalNone);
-            let e = e.rewrap(App(none, t.clone()));
-            return type_with(ctx, e);
-        }
-        OldOptionalLit(Some(x), t) => {
-            let optional = SubExpr::from_builtin(Builtin::Optional);
-            let x = x.rewrap(SomeLit(x.clone()));
-            let t = t.rewrap(App(optional, t.clone()));
-            let e = e.rewrap(Annot(x, t));
-            return type_with(ctx, e);
-        }
         Embed(p) => p.clone().into_typed(),
         Var(var) => match ctx.lookup(&var) {
             Some(typed) => typed,
@@ -423,12 +409,9 @@ fn type_last_layer(
     let mkerr = |msg: TypeMessage| TypeError::new(ctx, msg);
 
     match e {
-        Lam(_, _, _)
-        | Pi(_, _, _)
-        | Let(_, _, _, _)
-        | OldOptionalLit(_, _)
-        | Embed(_)
-        | Var(_) => unreachable!(),
+        Lam(_, _, _) | Pi(_, _, _) | Let(_, _, _, _) | Embed(_) | Var(_) => {
+            unreachable!()
+        }
         App(f, a) => {
             let tf = f.get_type()?;
             let (x, tx, tb) = match &tf.to_value() {
@@ -1296,8 +1279,6 @@ mod spec_tests {
     ti_success!(ti_success_unit_NaturalShow, "unit/NaturalShow");
     ti_success!(ti_success_unit_NaturalToInteger, "unit/NaturalToInteger");
     ti_success!(ti_success_unit_None, "unit/None");
-    ti_success!(ti_success_unit_OldOptionalNone, "unit/OldOptionalNone");
-    ti_success!(ti_success_unit_OldOptionalTrue, "unit/OldOptionalTrue");
     ti_success!(ti_success_unit_OperatorAnd, "unit/OperatorAnd");
     ti_success!(ti_success_unit_OperatorAndNormalizeArguments, "unit/OperatorAndNormalizeArguments");
     ti_success!(ti_success_unit_OperatorEqual, "unit/OperatorEqual");
diff --git a/dhall_generated_parser/src/dhall.pest.visibility b/dhall_generated_parser/src/dhall.pest.visibility
index 60de54d..0c48656 100644
--- a/dhall_generated_parser/src/dhall.pest.visibility
+++ b/dhall_generated_parser/src/dhall.pest.visibility
@@ -134,8 +134,6 @@ import
 expression
 annotated_expression
 let_binding
-empty_collection
-non_empty_optional
 # operator_expression
 import_alt_expression
 or_expression
diff --git a/dhall_syntax/src/core/expr.rs b/dhall_syntax/src/core/expr.rs
index da9465d..df2dc97 100644
--- a/dhall_syntax/src/core/expr.rs
+++ b/dhall_syntax/src/core/expr.rs
@@ -194,10 +194,6 @@ pub enum ExprF<SubExpr, Embed> {
     EmptyListLit(SubExpr),
     ///  `[x, y, z]`
     NEListLit(Vec<SubExpr>),
-    /// Deprecated Optional literal form
-    ///  `[] : Optional a`
-    ///  `[x] : Optional a`
-    OldOptionalLit(Option<SubExpr>, SubExpr),
     ///  `Some e`
     SomeLit(SubExpr),
     ///  `{ k1 : t1, k2 : t1 }`
diff --git a/dhall_syntax/src/core/visitor.rs b/dhall_syntax/src/core/visitor.rs
index 99a9c11..1745fdb 100644
--- a/dhall_syntax/src/core/visitor.rs
+++ b/dhall_syntax/src/core/visitor.rs
@@ -137,10 +137,6 @@ where
             ),
             EmptyListLit(t) => EmptyListLit(v.visit_subexpr(t)?),
             NEListLit(es) => NEListLit(vec(es, |e| v.visit_subexpr(e))?),
-            OldOptionalLit(x, t) => OldOptionalLit(
-                opt(x, |e| v.visit_subexpr(e))?,
-                v.visit_subexpr(t)?,
-            ),
             SomeLit(e) => SomeLit(v.visit_subexpr(e)?),
             RecordType(kts) => RecordType(dupmap(kts, v)?),
             RecordLit(kvs) => RecordLit(dupmap(kvs, v)?),
diff --git a/dhall_syntax/src/parser.rs b/dhall_syntax/src/parser.rs
index 9d9a374..db1699b 100644
--- a/dhall_syntax/src/parser.rs
+++ b/dhall_syntax/src/parser.rs
@@ -724,6 +724,9 @@ make_parser! {
         [merge(()), expression(x), expression(y), expression(z)] => {
             spanned(span, Merge(x, y, Some(z)))
         },
+        [List(()), expression(x)] => {
+            spanned(span, EmptyListLit(x))
+        },
         [expression(e)] => e,
     ));
 
@@ -738,21 +741,6 @@ make_parser! {
     token_rule!(List<()>);
     token_rule!(Optional<()>);
 
-    rule!(empty_collection<ParsedSubExpr> as expression; span; children!(
-        [List(_), expression(t)] => {
-            spanned(span, EmptyListLit(t))
-        },
-        [Optional(_), expression(t)] => {
-            spanned(span, OldOptionalLit(None, t))
-        },
-    ));
-
-    rule!(non_empty_optional<ParsedSubExpr> as expression; span; children!(
-        [expression(x), Optional(_), expression(t)] => {
-            spanned(span, OldOptionalLit(Some(x), t))
-        }
-    ));
-
     rule!(import_alt_expression<ParsedSubExpr> as expression; children!(
         [expression(e)] => e,
         [expression(first), expression(rest)..] => {
diff --git a/dhall_syntax/src/printer.rs b/dhall_syntax/src/printer.rs
index dbed55d..b585a5b 100644
--- a/dhall_syntax/src/printer.rs
+++ b/dhall_syntax/src/printer.rs
@@ -32,12 +32,6 @@ impl<SE: Display + Clone, E: Display> Display for ExprF<SE, E> {
             NEListLit(es) => {
                 fmt_list("[", ", ", "]", es, f, Display::fmt)?;
             }
-            OldOptionalLit(None, t) => {
-                write!(f, "[] : Optional {}", t)?;
-            }
-            OldOptionalLit(Some(x), t) => {
-                write!(f, "[{}] : Optional {}", x, t)?;
-            }
             SomeLit(e) => {
                 write!(f, "Some {}", e)?;
             }
@@ -154,7 +148,6 @@ impl<S: Clone, A: Display + Clone> Expr<S, A> {
             | Let(_, _, _, _)
             | EmptyListLit(_)
             | NEListLit(_)
-            | OldOptionalLit(_, _)
             | SomeLit(_)
             | Merge(_, _, _)
             | Annot(_, _)
@@ -190,7 +183,6 @@ impl<S: Clone, A: Display + Clone> Expr<S, A> {
                 b.phase(PrintPhase::BinOp(op)),
             ),
             EmptyListLit(t) => EmptyListLit(t.phase(Import)),
-            OldOptionalLit(x, t) => OldOptionalLit(x, t.phase(Import)),
             SomeLit(e) => SomeLit(e.phase(Import)),
             ExprF::App(f, a) => ExprF::App(f.phase(Import), a.phase(Import)),
             Field(a, b) => Field(a.phase(Primitive), b),