From 5c342a5688fe7a4bb337ce0622968226d524022e Mon Sep 17 00:00:00 2001
From: Nadrieril
Date: Sun, 9 Feb 2020 15:32:27 +0000
Subject: Resolve by ref instead of by mut

---
 dhall/src/syntax/ast/expr.rs | 53 ++++----------------------------------------
 1 file changed, 4 insertions(+), 49 deletions(-)

(limited to 'dhall/src/syntax/ast/expr.rs')

diff --git a/dhall/src/syntax/ast/expr.rs b/dhall/src/syntax/ast/expr.rs
index b493fdb..420df5b 100644
--- a/dhall/src/syntax/ast/expr.rs
+++ b/dhall/src/syntax/ast/expr.rs
@@ -1,5 +1,5 @@
 use crate::syntax::map::{DupTreeMap, DupTreeSet};
-use crate::syntax::visitor::{self, ExprKindMutVisitor, ExprKindVisitor};
+use crate::syntax::visitor::{self, ExprKindVisitor};
 use crate::syntax::*;
 
 pub type Integer = isize;
@@ -208,13 +208,6 @@ impl<SE, E> ExprKind<SE, E> {
         self.traverse_ref_maybe_binder(|_, e| visit_subexpr(e))
     }
 
-    fn traverse_mut<'a, Err>(
-        &'a mut self,
-        visit_subexpr: impl FnMut(&'a mut SE) -> Result<(), Err>,
-    ) -> Result<(), Err> {
-        visitor::TraverseMutVisitor { visit_subexpr }.visit(self)
-    }
-
     pub fn map_ref_maybe_binder<'a, SE2>(
         &'a self,
         mut map: impl FnMut(Option<&'a Label>, &'a SE) -> SE2,
@@ -248,16 +241,15 @@ impl<SE, E> ExprKind<SE, E> {
     {
         self.map_ref_maybe_binder(|_, e| map_subexpr(e))
     }
-
-    pub fn map_mut<'a>(&'a mut self, mut map_subexpr: impl FnMut(&'a mut SE)) {
-        trivial_result(self.traverse_mut(|x| Ok(map_subexpr(x))))
-    }
 }
 
 impl<E> Expr<E> {
     pub fn as_ref(&self) -> &UnspannedExpr<E> {
         &self.kind
     }
+    pub fn kind(&self) -> &UnspannedExpr<E> {
+        &self.kind
+    }
     pub fn span(&self) -> Span {
         self.span.clone()
     }
@@ -281,43 +273,6 @@ impl<E> Expr<E> {
             span,
         }
     }
-
-    pub fn traverse_resolve_mut<Err, F1>(
-        &mut self,
-        f: &mut F1,
-    ) -> Result<(), Err>
-    where
-        E: Clone,
-        F1: FnMut(Import<Expr<E>>) -> Result<E, Err>,
-    {
-        match self.kind.as_mut() {
-            ExprKind::BinOp(BinOp::ImportAlt, l, r) => {
-                let garbage_expr = ExprKind::BoolLit(false);
-                let new_self = if l.traverse_resolve_mut(f).is_ok() {
-                    l
-                } else {
-                    r.traverse_resolve_mut(f)?;
-                    r
-                };
-                *self.kind =
-                    std::mem::replace(new_self.kind.as_mut(), garbage_expr);
-            }
-            _ => {
-                self.kind.traverse_mut(|e| e.traverse_resolve_mut(f))?;
-                if let ExprKind::Import(import) = self.kind.as_mut() {
-                    let garbage_import = Import {
-                        mode: ImportMode::Code,
-                        location: ImportLocation::Missing,
-                        hash: None,
-                    };
-                    // Move out of &mut import
-                    let import = std::mem::replace(import, garbage_import);
-                    *self.kind = ExprKind::Embed(f(import)?);
-                }
-            }
-        }
-        Ok(())
-    }
 }
 
 pub fn trivial_result<T>(x: Result<T, !>) -> T {
-- 
cgit v1.2.3


From 5a2538d174fd36a8ed7f4fa344b9583fc48bd977 Mon Sep 17 00:00:00 2001
From: Nadrieril
Date: Tue, 11 Feb 2020 13:12:13 +0000
Subject: Remove the Embed variant from ExprKind

---
 dhall/src/syntax/ast/expr.rs | 58 +++++++++++++++-----------------------------
 1 file changed, 19 insertions(+), 39 deletions(-)

(limited to 'dhall/src/syntax/ast/expr.rs')

diff --git a/dhall/src/syntax/ast/expr.rs b/dhall/src/syntax/ast/expr.rs
index 420df5b..722630f 100644
--- a/dhall/src/syntax/ast/expr.rs
+++ b/dhall/src/syntax/ast/expr.rs
@@ -96,19 +96,19 @@ pub enum Builtin {
 
 // Each node carries an annotation.
 #[derive(Debug, Clone)]
-pub struct Expr<Embed> {
-    kind: Box<ExprKind<Expr<Embed>, Embed>>,
+pub struct Expr {
+    kind: Box<ExprKind<Expr>>,
     span: Span,
 }
 
-pub type UnspannedExpr<Embed> = ExprKind<Expr<Embed>, Embed>;
+pub type UnspannedExpr = ExprKind<Expr>;
 
 /// Syntax tree for expressions
 // Having the recursion out of the enum definition enables writing
 // much more generic code and improves pattern-matching behind
 // smart pointers.
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
-pub enum ExprKind<SubExpr, Embed> {
+pub enum ExprKind<SubExpr> {
     Const(Const),
     ///  `x`
     ///  `x@n`
@@ -169,18 +169,13 @@ pub enum ExprKind<SubExpr, Embed> {
     Completion(SubExpr, SubExpr),
     /// `./some/path`
     Import(Import<SubExpr>),
-    /// Embeds the result of resolving an import
-    Embed(Embed),
 }
 
-impl<SE, E> ExprKind<SE, E> {
+impl<SE> ExprKind<SE> {
     pub fn traverse_ref_maybe_binder<'a, SE2, Err>(
         &'a self,
         visit: impl FnMut(Option<&'a Label>, &'a SE) -> Result<SE2, Err>,
-    ) -> Result<ExprKind<SE2, E>, Err>
-    where
-        E: Clone,
-    {
+    ) -> Result<ExprKind<SE2>, Err> {
         visitor::TraverseRefMaybeBinderVisitor(visit).visit(self)
     }
 
@@ -188,10 +183,7 @@ impl<SE, E> ExprKind<SE, E> {
         &'a self,
         mut visit_subexpr: impl FnMut(&'a SE) -> Result<SE2, Err>,
         mut visit_under_binder: impl FnMut(&'a Label, &'a SE) -> Result<SE2, Err>,
-    ) -> Result<ExprKind<SE2, E>, Err>
-    where
-        E: Clone,
-    {
+    ) -> Result<ExprKind<SE2>, Err> {
         self.traverse_ref_maybe_binder(|l, x| match l {
             None => visit_subexpr(x),
             Some(l) => visit_under_binder(l, x),
@@ -201,20 +193,14 @@ impl<SE, E> ExprKind<SE, E> {
     pub(crate) fn traverse_ref<'a, SE2, Err>(
         &'a self,
         mut visit_subexpr: impl FnMut(&'a SE) -> Result<SE2, Err>,
-    ) -> Result<ExprKind<SE2, E>, Err>
-    where
-        E: Clone,
-    {
+    ) -> Result<ExprKind<SE2>, Err> {
         self.traverse_ref_maybe_binder(|_, e| visit_subexpr(e))
     }
 
     pub fn map_ref_maybe_binder<'a, SE2>(
         &'a self,
         mut map: impl FnMut(Option<&'a Label>, &'a SE) -> SE2,
-    ) -> ExprKind<SE2, E>
-    where
-        E: Clone,
-    {
+    ) -> ExprKind<SE2> {
         trivial_result(self.traverse_ref_maybe_binder(|l, x| Ok(map(l, x))))
     }
 
@@ -222,10 +208,7 @@ impl<SE, E> ExprKind<SE, E> {
         &'a self,
         mut map_subexpr: impl FnMut(&'a SE) -> SE2,
         mut map_under_binder: impl FnMut(&'a Label, &'a SE) -> SE2,
-    ) -> ExprKind<SE2, E>
-    where
-        E: Clone,
-    {
+    ) -> ExprKind<SE2> {
         self.map_ref_maybe_binder(|l, x| match l {
             None => map_subexpr(x),
             Some(l) => map_under_binder(l, x),
@@ -235,33 +218,30 @@ impl<SE, E> ExprKind<SE, E> {
     pub fn map_ref<'a, SE2>(
         &'a self,
         mut map_subexpr: impl FnMut(&'a SE) -> SE2,
-    ) -> ExprKind<SE2, E>
-    where
-        E: Clone,
-    {
+    ) -> ExprKind<SE2> {
         self.map_ref_maybe_binder(|_, e| map_subexpr(e))
     }
 }
 
-impl<E> Expr<E> {
-    pub fn as_ref(&self) -> &UnspannedExpr<E> {
+impl Expr {
+    pub fn as_ref(&self) -> &UnspannedExpr {
         &self.kind
     }
-    pub fn kind(&self) -> &UnspannedExpr<E> {
+    pub fn kind(&self) -> &UnspannedExpr {
         &self.kind
     }
     pub fn span(&self) -> Span {
         self.span.clone()
     }
 
-    pub fn new(kind: UnspannedExpr<E>, span: Span) -> Self {
+    pub fn new(kind: UnspannedExpr, span: Span) -> Self {
         Expr {
             kind: Box::new(kind),
             span,
         }
     }
 
-    pub fn rewrap<E2>(&self, kind: UnspannedExpr<E2>) -> Expr<E2> {
+    pub fn rewrap(&self, kind: UnspannedExpr) -> Expr {
         Expr {
             kind: Box::new(kind),
             span: self.span.clone(),
@@ -317,15 +297,15 @@ impl From<Label> for V {
     }
 }
 
-impl<Embed: PartialEq> std::cmp::PartialEq for Expr<Embed> {
+impl std::cmp::PartialEq for Expr {
     fn eq(&self, other: &Self) -> bool {
         self.kind == other.kind
     }
 }
 
-impl<Embed: Eq> std::cmp::Eq for Expr<Embed> {}
+impl std::cmp::Eq for Expr {}
 
-impl<Embed: std::hash::Hash> std::hash::Hash for Expr<Embed> {
+impl std::hash::Hash for Expr {
     fn hash<H>(&self, state: &mut H)
     where
         H: std::hash::Hasher,
-- 
cgit v1.2.3


From cab75190e86e8fd4ccc209499c0e7f300a669022 Mon Sep 17 00:00:00 2001
From: Nadrieril
Date: Tue, 11 Feb 2020 13:33:17 +0000
Subject: Simplify ExprKind visitor

---
 dhall/src/syntax/ast/expr.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

(limited to 'dhall/src/syntax/ast/expr.rs')

diff --git a/dhall/src/syntax/ast/expr.rs b/dhall/src/syntax/ast/expr.rs
index 722630f..512010a 100644
--- a/dhall/src/syntax/ast/expr.rs
+++ b/dhall/src/syntax/ast/expr.rs
@@ -1,5 +1,5 @@
 use crate::syntax::map::{DupTreeMap, DupTreeSet};
-use crate::syntax::visitor::{self, ExprKindVisitor};
+use crate::syntax::visitor;
 use crate::syntax::*;
 
 pub type Integer = isize;
@@ -176,7 +176,7 @@ impl<SE> ExprKind<SE> {
         &'a self,
         visit: impl FnMut(Option<&'a Label>, &'a SE) -> Result<SE2, Err>,
     ) -> Result<ExprKind<SE2>, Err> {
-        visitor::TraverseRefMaybeBinderVisitor(visit).visit(self)
+        visitor::visit_ref(self, visit)
     }
 
     pub fn traverse_ref_with_special_handling_of_binders<'a, SE2, Err>(
-- 
cgit v1.2.3


From 40bee3cdcb9ac0c76996feeceb6ca160a6bd8b42 Mon Sep 17 00:00:00 2001
From: Nadrieril
Date: Tue, 11 Feb 2020 19:04:44 +0000
Subject: Introduce LitKind to factor out common enum nodes

---
 dhall/src/syntax/ast/expr.rs | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

(limited to 'dhall/src/syntax/ast/expr.rs')

diff --git a/dhall/src/syntax/ast/expr.rs b/dhall/src/syntax/ast/expr.rs
index 512010a..18ec9fd 100644
--- a/dhall/src/syntax/ast/expr.rs
+++ b/dhall/src/syntax/ast/expr.rs
@@ -103,6 +103,19 @@ pub struct Expr {
 
 pub type UnspannedExpr = ExprKind<Expr>;
 
+/// Simple literals
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub enum LitKind {
+    ///  `True`
+    Bool(bool),
+    ///  `1`
+    Natural(Natural),
+    ///  `+2`
+    Integer(Integer),
+    ///  `3.24`
+    Double(Double),
+}
+
 /// Syntax tree for expressions
 // Having the recursion out of the enum definition enables writing
 // much more generic code and improves pattern-matching behind
@@ -110,6 +123,7 @@ pub type UnspannedExpr = ExprKind<Expr>;
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub enum ExprKind<SubExpr> {
     Const(Const),
+    Lit(LitKind),
     ///  `x`
     ///  `x@n`
     Var(V),
@@ -131,16 +145,8 @@ pub enum ExprKind<SubExpr> {
     Builtin(Builtin),
     // Binary operations
     BinOp(BinOp, SubExpr, SubExpr),
-    ///  `True`
-    BoolLit(bool),
     ///  `if x then y else z`
     BoolIf(SubExpr, SubExpr, SubExpr),
-    ///  `1`
-    NaturalLit(Natural),
-    ///  `+2`
-    IntegerLit(Integer),
-    ///  `3.24`
-    DoubleLit(Double),
     ///  `"Some ${interpolated} text"`
     TextLit(InterpolatedText<SubExpr>),
     ///  `[] : t`
-- 
cgit v1.2.3


From 130de8cea49c848a06174c61c747d9414a5c71b7 Mon Sep 17 00:00:00 2001
From: Nadrieril
Date: Sun, 16 Feb 2020 19:06:23 +0000
Subject: Start requiring Universe to build a Type

---
 dhall/src/syntax/ast/expr.rs | 7 +++++++
 1 file changed, 7 insertions(+)

(limited to 'dhall/src/syntax/ast/expr.rs')

diff --git a/dhall/src/syntax/ast/expr.rs b/dhall/src/syntax/ast/expr.rs
index 18ec9fd..a479b53 100644
--- a/dhall/src/syntax/ast/expr.rs
+++ b/dhall/src/syntax/ast/expr.rs
@@ -1,3 +1,4 @@
+use crate::semantics::Universe;
 use crate::syntax::map::{DupTreeMap, DupTreeSet};
 use crate::syntax::visitor;
 use crate::syntax::*;
@@ -18,6 +19,12 @@ pub enum Const {
     Sort,
 }
 
+impl Const {
+    pub(crate) fn to_universe(self) -> Universe {
+        Universe::from_const(self)
+    }
+}
+
 /// Bound variable
 ///
 /// The `Label` field is the variable's name (i.e. \"`x`\").
-- 
cgit v1.2.3