Remove union literals from the language

10 files changed, 11 insertions, 104 deletions

diff --git a/dhall-lang b/dhall-lang
-Subproject 95cfb88db2f79b3c4bf61c76d9e9869d149cdef
+Subproject f692f70bafa0322da5d9c4b535b2d323a9c5ac6
diff --git a/dhall/src/core/value.rs b/dhall/src/core/value.rs
index f47f1b2..d7b9149 100644
--- a/dhall/src/core/value.rs
+++ b/dhall/src/core/value.rs
@@ -178,19 +178,10 @@ impl Value {
                     .collect();
                 rc(ExprF::Field(rc(ExprF::UnionType(kts)), l.clone()))
             }
-            Value::UnionLit(l, v, kts) => rc(ExprF::UnionLit(
-                l.clone(),
+            Value::UnionLit(l, v, kts) => rc(ExprF::App(
+                Value::UnionConstructor(l.clone(), kts.clone())
+                    .normalize_to_expr_maybe_alpha(alpha),
                 v.normalize_to_expr_maybe_alpha(alpha),
-                kts.iter()
-                    .map(|(k, v)| {
-                        (
-                            k.clone(),
-                            v.as_ref().map(|v| {
-                                v.normalize_to_expr_maybe_alpha(alpha)
-                            }),
-                        )
-                    })
-                    .collect(),
             )),
             Value::TextLit(elts) => {
                 use InterpolatedTextContents::{Expr, Text};
diff --git a/dhall/src/phase/binary.rs b/dhall/src/phase/binary.rs
index e44b1e2..bfe217f 100644
--- a/dhall/src/phase/binary.rs
+++ b/dhall/src/phase/binary.rs
@@ -160,12 +160,9 @@ fn cbor_value_to_dhall(
                 let map = cbor_map_to_dhall_opt_map(map)?;
                 UnionType(map)
             }
-            [U64(12), String(l), x, Object(map)] => {
-                let map = cbor_map_to_dhall_opt_map(map)?;
-                let x = cbor_value_to_dhall(&x)?;
-                let l = Label::from(l.as_str());
-                UnionLit(l, x, map)
-            }
+            [U64(12), ..] => Err(DecodeError::WrongFormatError(
+                "Union literals are not supported anymore".to_owned(),
+            ))?,
             [U64(14), x, y, z] => {
                 let x = cbor_value_to_dhall(&x)?;
                 let y = cbor_value_to_dhall(&y)?;
@@ -496,9 +493,6 @@ where
         RecordType(map) => ser_seq!(ser; tag(7), RecordMap(map)),
         RecordLit(map) => ser_seq!(ser; tag(8), RecordMap(map)),
         UnionType(map) => ser_seq!(ser; tag(11), UnionMap(map)),
-        UnionLit(l, x, map) => {
-            ser_seq!(ser; tag(12), label(l), expr(x), UnionMap(map))
-        }
         Field(x, l) => ser_seq!(ser; tag(9), expr(x), label(l)),
         BinOp(op, x, y) => {
             use dhall_syntax::BinOp::*;
diff --git a/dhall/src/phase/normalize.rs b/dhall/src/phase/normalize.rs
index 2e9f258..3e45240 100644
--- a/dhall/src/phase/normalize.rs
+++ b/dhall/src/phase/normalize.rs
@@ -677,13 +677,6 @@ pub fn normalize_one_layer(expr: ExprF<Thunk, X>) -> Value {
                 .map(|(k, t)| (k, TypeThunk::from_thunk(t)))
                 .collect(),
         )),
-        ExprF::UnionLit(l, x, kts) => Ret::Value(UnionLit(
-            l,
-            x,
-            kts.into_iter()
-                .map(|(k, t)| (k, t.map(|t| TypeThunk::from_thunk(t))))
-                .collect(),
-        )),
         ExprF::UnionType(kts) => Ret::Value(UnionType(
             kts.into_iter()
                 .map(|(k, t)| (k, t.map(|t| TypeThunk::from_thunk(t))))
diff --git a/dhall/src/phase/typecheck.rs b/dhall/src/phase/typecheck.rs
index 35bf3a9..4b3a03f 100644
--- a/dhall/src/phase/typecheck.rs
+++ b/dhall/src/phase/typecheck.rs
@@ -505,15 +505,6 @@ fn type_last_layer(
             )?
             .into_type(),
         )),
-        UnionLit(x, v, kvs) => {
-            use std::iter::once;
-            let kts = kvs
-                .iter()
-                .map(|(x, v)| Ok((x.clone(), v.as_ref().map(|v| v.to_type()))));
-            let t = v.get_type()?.into_owned();
-            let kts = kts.chain(once(Ok((x.clone(), Some(t)))));
-            Ok(RetTypeOnly(tck_union_type(ctx, kts)?.to_type()))
-        }
         Field(r, x) => {
             match &r.get_type()?.to_value() {
                 Value::RecordType(kts) => match kts.get(&x) {
diff --git a/dhall_generated_parser/src/dhall.pest.visibility b/dhall_generated_parser/src/dhall.pest.visibility
index 33018ae..dd54578 100644
--- a/dhall_generated_parser/src/dhall.pest.visibility
+++ b/dhall_generated_parser/src/dhall.pest.visibility
@@ -169,11 +169,9 @@ non_empty_record_type
 record_type_entry
 non_empty_record_literal
 record_literal_entry
-union_type_or_literal
+union_type
 empty_union_type
-non_empty_union_type_or_literal
-union_literal_variant_value
+# non_empty_union_type
 union_type_entry
-union_type_or_literal_variant_type
 non_empty_list_literal
 # complete_expression
diff --git a/dhall_syntax/src/core/expr.rs b/dhall_syntax/src/core/expr.rs
index 668ab45..aab4b6a 100644
--- a/dhall_syntax/src/core/expr.rs
+++ b/dhall_syntax/src/core/expr.rs
@@ -202,8 +202,6 @@ pub enum ExprF<SubExpr, Embed> {
     RecordLit(DupTreeMap<Label, SubExpr>),
     ///  `< k1 : t1, k2 >`
     UnionType(DupTreeMap<Label, Option<SubExpr>>),
-    ///  `< k1 = t1, k2 : t2, k3 >`
-    UnionLit(Label, SubExpr, DupTreeMap<Label, Option<SubExpr>>),
     ///  `merge x y : t`
     Merge(SubExpr, SubExpr, Option<SubExpr>),
     ///  `e.x`
diff --git a/dhall_syntax/src/core/visitor.rs b/dhall_syntax/src/core/visitor.rs
index b02544f..68ad956 100644
--- a/dhall_syntax/src/core/visitor.rs
+++ b/dhall_syntax/src/core/visitor.rs
@@ -141,9 +141,6 @@ where
             RecordType(kts) => RecordType(dupmap(kts, v)?),
             RecordLit(kvs) => RecordLit(dupmap(kvs, v)?),
             UnionType(kts) => UnionType(optdupmap(kts, v)?),
-            UnionLit(k, x, kts) => {
-                UnionLit(k.clone(), v.visit_subexpr(x)?, optdupmap(kts, v)?)
-            }
             Merge(x, y, t) => Merge(
                 v.visit_subexpr(x)?,
                 v.visit_subexpr(y)?,
diff --git a/dhall_syntax/src/parser.rs b/dhall_syntax/src/parser.rs
index 8336c74..a7f419a 100644
--- a/dhall_syntax/src/parser.rs
+++ b/dhall_syntax/src/parser.rs
@@ -976,67 +976,22 @@ make_parser! {
         [label(name), expression(expr)] => (name, expr)
     ));
 
-    rule!(union_type_or_literal<ParsedSubExpr> as expression; span; children!(
+    rule!(union_type<ParsedSubExpr> as expression; span; children!(
         [empty_union_type(_)] => {
             spanned(span, UnionType(Default::default()))
         },
-        [non_empty_union_type_or_literal((Some((l, e)), entries))] => {
-            spanned(span, UnionLit(l, e, entries))
-        },
-        [non_empty_union_type_or_literal((None, entries))] => {
-            spanned(span, UnionType(entries))
+        [union_type_entry(entries)..] => {
+            spanned(span, UnionType(entries.collect()))
         },
     ));
 
     token_rule!(empty_union_type<()>);
 
-    rule!(non_empty_union_type_or_literal
-          <(Option<(Label, ParsedSubExpr)>,
-            DupTreeMap<Label, Option<ParsedSubExpr>>)>;
-            children!(
-        [label(l), union_literal_variant_value((e, entries))] => {
-            (Some((l, e)), entries)
-        },
-        [label(l), union_type_or_literal_variant_type((e, rest))] => {
-            let (x, mut entries) = rest;
-            entries.insert(l, e);
-            (x, entries)
-        },
-    ));
-
-    rule!(union_literal_variant_value
-          <(ParsedSubExpr, DupTreeMap<Label, Option<ParsedSubExpr>>)>;
-            children!(
-        [expression(e), union_type_entry(entries)..] => {
-            (e, entries.collect())
-        },
-    ));
-
     rule!(union_type_entry<(Label, Option<ParsedSubExpr>)>; children!(
         [label(name), expression(expr)] => (name, Some(expr)),
         [label(name)] => (name, None),
     ));
 
-    // TODO: unary union variants
-    rule!(union_type_or_literal_variant_type
-          <(Option<ParsedSubExpr>,
-            (Option<(Label, ParsedSubExpr)>,
-             DupTreeMap<Label, Option<ParsedSubExpr>>))>;
-                children!(
-        [expression(e), non_empty_union_type_or_literal(rest)] => {
-            (Some(e), rest)
-        },
-        [expression(e)] => {
-            (Some(e), (None, Default::default()))
-        },
-        [non_empty_union_type_or_literal(rest)] => {
-            (None, rest)
-        },
-        [] => {
-            (None, (None, Default::default()))
-        },
-    ));
-
     rule!(non_empty_list_literal<ParsedSubExpr> as expression; span;
           children!(
         [expression(items)..] => spanned(
diff --git a/dhall_syntax/src/printer.rs b/dhall_syntax/src/printer.rs
index 52d3d81..db688bd 100644
--- a/dhall_syntax/src/printer.rs
+++ b/dhall_syntax/src/printer.rs
@@ -85,16 +85,6 @@ impl<SE: Display + Clone, E: Display> Display for ExprF<SE, E> {
                 }
                 Ok(())
             })?,
-            UnionLit(a, b, c) => {
-                write!(f, "< {} = {}", a, b)?;
-                for (k, v) in c {
-                    write!(f, " | {}", k)?;
-                    if let Some(v) = v {
-                        write!(f, ": {}", v)?;
-                    }
-                }
-                f.write_str(" >")?
-            }
             Embed(a) => a.fmt(f)?,
         }
         Ok(())