Expose simple::Val/Ty properly in the API

7 files changed, 132 insertions, 169 deletions

diff --git a/README.md b/README.md
index 1bcf558..2cb3c0b 100644
--- a/README.md
+++ b/README.md
@@ -169,7 +169,7 @@ same name as the corresponding test.
 
 #### [???]
 
-- Breaking change: use `serde_dhall::Type` type for type-checking instead of `serde_dhall::Value`
+- Breaking change: use `serde_dhall::simple::Type` type for type-checking instead of `serde_dhall::Value`
 
 #### [0.4.0]
 
diff --git a/dhall_proc_macros/src/derive.rs b/dhall_proc_macros/src/derive.rs
index 4885b49..f7edf3a 100644
--- a/dhall_proc_macros/src/derive.rs
+++ b/dhall_proc_macros/src/derive.rs
@@ -52,9 +52,11 @@ fn derive_for_struct(
         let ty = static_type(ty);
         quote!( (#name.to_owned(), #ty) )
     });
-    Ok(quote! { ::serde_dhall::simple::Type::make_record_type(
-        vec![ #(#entries),* ].into_iter()
-    ) })
+    Ok(quote! {
+        ::serde_dhall::simple::TyKind::Record(
+            vec![ #(#entries),* ].into_iter().collect()
+        ).into()
+    })
 }
 
 fn derive_for_enum(
@@ -89,9 +91,11 @@ fn derive_for_enum(
         })
         .collect::<Result<_, Error>>()?;
 
-    Ok(quote! { ::serde_dhall::simple::Type::make_union_type(
-        vec![ #(#entries),* ].into_iter()
-    ) })
+    Ok(quote! {
+        ::serde_dhall::simple::TyKind::Union(
+            vec![ #(#entries),* ].into_iter().collect()
+        ).into()
+    })
 }
 
 pub fn derive_static_type_inner(
@@ -164,8 +168,7 @@ pub fn derive_static_type_inner(
         impl #impl_generics ::serde_dhall::StaticType
                 for #ident #ty_generics
                 #where_clause {
-            fn static_type() ->
-                    ::serde_dhall::simple::Type {
+            fn static_type() -> ::serde_dhall::simple::Type {
                 #(#assertions)*
                 #get_type
             }
diff --git a/serde_dhall/src/lib.rs b/serde_dhall/src/lib.rs
index adc242f..4b1a689 100644
--- a/serde_dhall/src/lib.rs
+++ b/serde_dhall/src/lib.rs
@@ -16,7 +16,7 @@
 //!
 //! # Basic usage
 //!
-//! The main entrypoint of this library is the [`from_str`][from_str] function. It reads a string
+//! The main entrypoint of this library is the [`from_str`](fn.from_str.html) function. It reads a string
 //! containing a Dhall expression and deserializes it into any serde-compatible type.
 //!
 //! This could mean a common Rust type like `HashMap`:
@@ -88,11 +88,11 @@
 //!
 //! # Replacing `serde_json` or `serde_yaml`
 //!
-//! If you used to consume JSON or YAML, you only need to replace [serde_json::from_str] or
-//! [serde_yaml::from_str] with [serde_dhall::from_str][from_str].
+//! If you used to consume JSON or YAML, you only need to replace [`serde_json::from_str`] or
+//! [`serde_yaml::from_str`] with [`serde_dhall::from_str`](fn.from_str.html).
 //!
-//! [serde_json::from_str]: https://docs.serde.rs/serde_json/de/fn.from_str.html
-//! [serde_yaml::from_str]: https://docs.serde.rs/serde_yaml/fn.from_str.html
+//! [`serde_json::from_str`]: https://docs.serde.rs/serde_json/fn.from_str.html
+//! [`serde_yaml::from_str`]: https://docs.serde.rs/serde_yaml/fn.from_str.html
 //!
 //!
 //! # Additional Dhall typechecking
@@ -106,8 +106,8 @@
 //! There are two ways to typecheck a Dhall value: you can provide the type as Dhall text or you
 //! can let Rust infer it for you.
 //!
-//! To provide a type written in Dhall, first parse it into a [`serde_dhall::Type`][Type], then
-//! pass it to [`from_str_check_type`][from_str_check_type].
+//! To provide a type written in Dhall, first parse it into a [`simple::Type`](simple/struct.Type.html), then
+//! pass it to [`from_str_check_type`](fn.from_str_check_type.html).
 //!
 //! ```rust
 //! # fn main() -> serde_dhall::Result<()> {
@@ -135,7 +135,8 @@
 //! # }
 //! ```
 //!
-//! You can also let Rust infer the appropriate Dhall type, using the [StaticType] trait.
+//! You can also let Rust infer the appropriate Dhall type, using the
+//! [StaticType](trait.StaticType.html) trait.
 //!
 //! ```rust
 //! # fn main() -> serde_dhall::Result<()> {
@@ -169,18 +170,19 @@
 
 mod error;
 mod serde;
+/// Serde-compatible values and their type
 pub mod simple;
 mod static_type;
-mod value;
+/// Arbitrary Dhall values
+pub mod value;
 
+pub use crate::simple::{Type as SimpleType, Value as SimpleValue};
 #[doc(hidden)]
 pub use dhall_proc_macros::StaticType;
 pub use error::{Error, Result};
 pub use static_type::StaticType;
 pub use value::Value;
 
-use simple::Type;
-
 pub(crate) mod sealed {
     pub trait Sealed {}
 }
@@ -196,12 +198,11 @@ pub trait Deserialize: sealed::Sealed + Sized {
     fn from_dhall(v: &Value) -> Result<Self>;
 }
 
-fn from_str_with_annot<T>(s: &str, ty: Option<&Type>) -> Result<T>
+fn from_str_with_annot<T>(s: &str, ty: Option<&simple::Type>) -> Result<T>
 where
     T: Deserialize,
 {
-    let ty = ty.map(|ty| ty.to_value());
-    let val = Value::from_str_with_annot(s, ty.as_ref())?;
+    let val = Value::from_str_with_annot(s, ty)?;
     T::from_dhall(&val)
 }
 
@@ -223,7 +224,7 @@ where
 ///
 /// Like [from_str], but this additionally checks that
 /// the type of the provided expression matches the supplied type.
-pub fn from_str_check_type<T>(s: &str, ty: &Type) -> Result<T>
+pub fn from_str_check_type<T>(s: &str, ty: &simple::Type) -> Result<T>
 where
     T: Deserialize,
 {
diff --git a/serde_dhall/src/serde.rs b/serde_dhall/src/serde.rs
index 91ef5d7..717450a 100644
--- a/serde_dhall/src/serde.rs
+++ b/serde_dhall/src/serde.rs
@@ -6,7 +6,7 @@ use serde::de::value::{
 
 use dhall::syntax::NumKind;
 
-use crate::simple::{SValKind, SimpleValue};
+use crate::simple::{ValKind, Value as SimpleValue};
 use crate::{Deserialize, Error, Result, Value};
 
 impl<'a, T> crate::sealed::Sealed for T where T: serde::Deserialize<'a> {}
@@ -44,7 +44,7 @@ impl<'de: 'a, 'a> serde::Deserializer<'de> for Deserializer<'a> {
     {
         use std::convert::TryInto;
         use NumKind::*;
-        use SValKind::*;
+        use ValKind::*;
 
         let val = |x| Deserializer(Cow::Borrowed(x));
         match self.0.kind() {
@@ -97,7 +97,7 @@ impl<'de: 'a, 'a> serde::Deserializer<'de> for Deserializer<'a> {
         let val = |x| Deserializer(Cow::Borrowed(x));
         match self.0.kind() {
             // Blindly takes keys in sorted order.
-            SValKind::Record(m) => visitor
+            ValKind::Record(m) => visitor
                 .visit_seq(SeqDeserializer::new(m.iter().map(|(_, v)| val(v)))),
             _ => self.deserialize_any(visitor),
         }
diff --git a/serde_dhall/src/simple.rs b/serde_dhall/src/simple.rs
index 0b322ae..4cd4ab7 100644
--- a/serde_dhall/src/simple.rs
+++ b/serde_dhall/src/simple.rs
@@ -3,161 +3,114 @@ use std::collections::BTreeMap;
 use dhall::semantics::{Hir, HirKind, Nir, NirKind};
 use dhall::syntax::{Builtin, ExprKind, NumKind, Span};
 
-use crate::Error;
+use crate::{sealed::Sealed, Deserialize, Error, Result};
 
+/// A simple value of the kind that can be encoded/decoded with serde
 #[derive(Debug, Clone, PartialEq, Eq)]
-pub struct SimpleValue {
-    kind: Box<SValKind>,
+pub struct Value {
+    kind: Box<ValKind>,
 }
 
 #[derive(Debug, Clone, PartialEq, Eq)]
-pub enum SValKind {
+pub enum ValKind {
+    // TODO: redefine NumKind locally
     Num(NumKind),
     Text(String),
-    Optional(Option<SimpleValue>),
-    List(Vec<SimpleValue>),
-    Record(BTreeMap<String, SimpleValue>),
-    Union(String, Option<SimpleValue>),
+    Optional(Option<Value>),
+    List(Vec<Value>),
+    // TODO: HashMap ?
+    Record(BTreeMap<String, Value>),
+    Union(String, Option<Value>),
 }
 
+/// The type of a `simple::Value`.
 #[derive(Debug, Clone, PartialEq, Eq)]
-pub struct SimpleType {
-    kind: Box<STyKind>,
+pub struct Type {
+    kind: Box<TyKind>,
 }
 
 #[derive(Debug, Clone, PartialEq, Eq)]
-pub enum STyKind {
+pub enum TyKind {
     Bool,
     Natural,
     Integer,
     Double,
     Text,
-    Optional(SimpleType),
-    List(SimpleType),
-    Record(BTreeMap<String, SimpleType>),
-    Union(BTreeMap<String, Option<SimpleType>>),
+    Optional(Type),
+    List(Type),
+    Record(BTreeMap<String, Type>),
+    Union(BTreeMap<String, Option<Type>>),
 }
 
-/// A Dhall value. This is a wrapper around [`dhall::SimpleValue`].
-#[derive(Debug, Clone, PartialEq, Eq)]
-pub struct Value(SimpleValue);
-
-/// A Dhall type. This is a wrapper around [`dhall::SimpleType`].
-#[derive(Debug, Clone, PartialEq, Eq)]
-pub struct Type(SimpleType);
-
 impl Value {
-    pub fn into_simple_value(self) -> SimpleValue {
-        self.0
-    }
-}
-
-impl Type {
-    pub fn into_simple_type(self) -> SimpleType {
-        self.0
-    }
-    pub fn to_value(&self) -> crate::Value {
-        self.0.to_value()
-    }
-
-    pub(crate) fn from_simple_type(ty: SimpleType) -> Self {
-        Type(ty)
-    }
-    pub(crate) fn from_stykind(k: STyKind) -> Self {
-        Type(SimpleType::new(k))
-    }
-    pub(crate) fn make_optional_type(t: Type) -> Self {
-        Type::from_stykind(STyKind::Optional(t.0))
-    }
-    pub(crate) fn make_list_type(t: Type) -> Self {
-        Type::from_stykind(STyKind::List(t.0))
-    }
-    // Made public for the StaticType derive macro
-    #[doc(hidden)]
-    pub fn make_record_type(kts: impl Iterator<Item = (String, Type)>) -> Self {
-        Type::from_stykind(STyKind::Record(
-            kts.map(|(k, t)| (k, t.0)).collect(),
-        ))
-    }
-    #[doc(hidden)]
-    pub fn make_union_type(
-        kts: impl Iterator<Item = (String, Option<Type>)>,
-    ) -> Self {
-        Type::from_stykind(STyKind::Union(
-            kts.map(|(k, t)| (k, t.map(|t| t.0))).collect(),
-        ))
-    }
-}
-
-impl SimpleValue {
-    pub fn new(kind: SValKind) -> Self {
-        SimpleValue {
+    pub(crate) fn new(kind: ValKind) -> Self {
+        Value {
             kind: Box::new(kind),
         }
     }
-    pub fn from_nir(nir: &Nir) -> Option<Self> {
-        Some(SimpleValue::new(match nir.kind() {
-            NirKind::Num(lit) => SValKind::Num(lit.clone()),
-            NirKind::TextLit(x) => SValKind::Text(
+    pub(crate) fn from_nir(nir: &Nir) -> Option<Self> {
+        Some(Value::new(match nir.kind() {
+            NirKind::Num(lit) => ValKind::Num(lit.clone()),
+            NirKind::TextLit(x) => ValKind::Text(
                 x.as_text()
                     .expect("Normal form should ensure the text is a string"),
             ),
-            NirKind::EmptyOptionalLit(_) => SValKind::Optional(None),
+            NirKind::EmptyOptionalLit(_) => ValKind::Optional(None),
             NirKind::NEOptionalLit(x) => {
-                SValKind::Optional(Some(Self::from_nir(x)?))
+                ValKind::Optional(Some(Self::from_nir(x)?))
             }
-            NirKind::EmptyListLit(_) => SValKind::List(vec![]),
-            NirKind::NEListLit(xs) => SValKind::List(
+            NirKind::EmptyListLit(_) => ValKind::List(vec![]),
+            NirKind::NEListLit(xs) => ValKind::List(
                 xs.iter()
                     .map(|v| Self::from_nir(v))
                     .collect::<Option<_>>()?,
             ),
-            NirKind::RecordLit(kvs) => SValKind::Record(
+            NirKind::RecordLit(kvs) => ValKind::Record(
                 kvs.iter()
                     .map(|(k, v)| Some((k.into(), Self::from_nir(v)?)))
                     .collect::<Option<_>>()?,
             ),
             NirKind::UnionLit(field, x, _) => {
-                SValKind::Union(field.into(), Some(Self::from_nir(x)?))
+                ValKind::Union(field.into(), Some(Self::from_nir(x)?))
             }
             NirKind::UnionConstructor(field, ty)
                 if ty.get(field).map(|f| f.is_some()) == Some(false) =>
             {
-                SValKind::Union(field.into(), None)
+                ValKind::Union(field.into(), None)
             }
             _ => return None,
         }))
     }
 
-    pub fn kind(&self) -> &SValKind {
+    pub fn kind(&self) -> &ValKind {
         self.kind.as_ref()
     }
 }
 
-impl SimpleType {
-    pub fn new(kind: STyKind) -> Self {
-        SimpleType {
+impl Type {
+    pub fn new(kind: TyKind) -> Self {
+        Type {
             kind: Box::new(kind),
         }
     }
-    pub fn from_nir(nir: &Nir) -> Option<Self> {
-        Some(SimpleType::new(match nir.kind() {
+    pub(crate) fn from_nir(nir: &Nir) -> Option<Self> {
+        Some(Type::new(match nir.kind() {
             NirKind::BuiltinType(b) => match b {
-                Builtin::Bool => STyKind::Bool,
-                Builtin::Natural => STyKind::Natural,
-                Builtin::Integer => STyKind::Integer,
-                Builtin::Double => STyKind::Double,
-                Builtin::Text => STyKind::Text,
+                Builtin::Bool => TyKind::Bool,
+                Builtin::Natural => TyKind::Natural,
+                Builtin::Integer => TyKind::Integer,
+                Builtin::Double => TyKind::Double,
+                Builtin::Text => TyKind::Text,
                 _ => unreachable!(),
             },
-            NirKind::OptionalType(t) => STyKind::Optional(Self::from_nir(t)?),
-            NirKind::ListType(t) => STyKind::List(Self::from_nir(t)?),
-            NirKind::RecordType(kts) => STyKind::Record(
+            NirKind::OptionalType(t) => TyKind::Optional(Self::from_nir(t)?),
+            NirKind::ListType(t) => TyKind::List(Self::from_nir(t)?),
+            NirKind::RecordType(kts) => TyKind::Record(
                 kts.iter()
                     .map(|(k, v)| Some((k.into(), Self::from_nir(v)?)))
                     .collect::<Option<_>>()?,
             ),
-            NirKind::UnionType(kts) => STyKind::Union(
+            NirKind::UnionType(kts) => TyKind::Union(
                 kts.iter()
                     .map(|(k, v)| {
                         Some((
@@ -173,37 +126,37 @@ impl SimpleType {
         }))
     }
 
-    pub fn kind(&self) -> &STyKind {
+    pub fn kind(&self) -> &TyKind {
         self.kind.as_ref()
     }
-    pub fn to_value(&self) -> crate::Value {
-        crate::Value {
+    pub fn to_value(&self) -> crate::value::Value {
+        crate::value::Value {
             hir: self.to_hir(),
             as_simple_val: None,
             as_simple_ty: Some(self.clone()),
         }
     }
-    pub fn to_hir(&self) -> Hir {
+    pub(crate) fn to_hir(&self) -> Hir {
         let hir = |k| Hir::new(HirKind::Expr(k), Span::Artificial);
         hir(match self.kind() {
-            STyKind::Bool => ExprKind::Builtin(Builtin::Bool),
-            STyKind::Natural => ExprKind::Builtin(Builtin::Natural),
-            STyKind::Integer => ExprKind::Builtin(Builtin::Integer),
-            STyKind::Double => ExprKind::Builtin(Builtin::Double),
-            STyKind::Text => ExprKind::Builtin(Builtin::Text),
-            STyKind::Optional(t) => ExprKind::App(
+            TyKind::Bool => ExprKind::Builtin(Builtin::Bool),
+            TyKind::Natural => ExprKind::Builtin(Builtin::Natural),
+            TyKind::Integer => ExprKind::Builtin(Builtin::Integer),
+            TyKind::Double => ExprKind::Builtin(Builtin::Double),
+            TyKind::Text => ExprKind::Builtin(Builtin::Text),
+            TyKind::Optional(t) => ExprKind::App(
                 hir(ExprKind::Builtin(Builtin::Optional)),
                 t.to_hir(),
             ),
-            STyKind::List(t) => {
+            TyKind::List(t) => {
                 ExprKind::App(hir(ExprKind::Builtin(Builtin::List)), t.to_hir())
             }
-            STyKind::Record(kts) => ExprKind::RecordType(
+            TyKind::Record(kts) => ExprKind::RecordType(
                 kts.into_iter()
                     .map(|(k, t)| (k.as_str().into(), t.to_hir()))
                     .collect(),
             ),
-            STyKind::Union(kts) => ExprKind::UnionType(
+            TyKind::Union(kts) => ExprKind::UnionType(
                 kts.into_iter()
                     .map(|(k, t)| {
                         (k.as_str().into(), t.as_ref().map(|t| t.to_hir()))
@@ -214,30 +167,34 @@ impl SimpleType {
     }
 }
 
-impl super::sealed::Sealed for Value {}
+impl Sealed for Value {}
 
-impl super::Deserialize for Value {
-    fn from_dhall(v: &crate::Value) -> super::Result<Self> {
-        let sval = v.to_simple_value().ok_or_else(|| {
+impl Deserialize for Value {
+    fn from_dhall(v: &crate::value::Value) -> Result<Self> {
+        v.to_simple_value().ok_or_else(|| {
             Error::Deserialize(format!(
                 "this cannot be deserialized into a simple type: {}",
                 v
             ))
-        })?;
-        Ok(Value(sval))
+        })
     }
 }
 
-impl super::sealed::Sealed for Type {}
+impl Sealed for Type {}
 
-impl super::Deserialize for Type {
-    fn from_dhall(v: &crate::Value) -> super::Result<Self> {
-        let sty = v.to_simple_type().ok_or_else(|| {
+impl Deserialize for Type {
+    fn from_dhall(v: &crate::value::Value) -> Result<Self> {
+        v.to_simple_type().ok_or_else(|| {
             Error::Deserialize(format!(
                 "this cannot be deserialized into a simple type: {}",
                 v
             ))
-        })?;
-        Ok(Type(sty))
+        })
+    }
+}
+
+impl From<TyKind> for Type {
+    fn from(x: TyKind) -> Type {
+        Type::new(x)
     }
 }
diff --git a/serde_dhall/src/static_type.rs b/serde_dhall/src/static_type.rs
index 4e30f34..79418d2 100644
--- a/serde_dhall/src/static_type.rs
+++ b/serde_dhall/src/static_type.rs
@@ -1,5 +1,4 @@
-use crate::simple::{STyKind, SimpleType};
-use crate::Type;
+use crate::simple::{TyKind, Type};
 
 /// A Rust type that can be represented as a Dhall type.
 ///
@@ -20,7 +19,7 @@ macro_rules! derive_builtin {
     ($rust_ty:ty, $dhall_ty:ident) => {
         impl StaticType for $rust_ty {
             fn static_type() -> Type {
-                Type::from_simple_type(SimpleType::new(STyKind::$dhall_ty))
+                Type::new(TyKind::$dhall_ty)
             }
         }
     };
@@ -43,13 +42,15 @@ where
     B: StaticType,
 {
     fn static_type() -> Type {
-        Type::make_record_type(
+        TyKind::Record(
             vec![
                 ("_1".to_owned(), A::static_type()),
                 ("_2".to_owned(), B::static_type()),
             ]
-            .into_iter(),
+            .into_iter()
+            .collect(),
         )
+        .into()
     }
 }
 
@@ -59,13 +60,15 @@ where
     E: StaticType,
 {
     fn static_type() -> Type {
-        Type::make_union_type(
+        TyKind::Union(
             vec![
                 ("Ok".to_owned(), Some(T::static_type())),
                 ("Err".to_owned(), Some(E::static_type())),
             ]
-            .into_iter(),
+            .into_iter()
+            .collect(),
         )
+        .into()
     }
 }
 
@@ -74,7 +77,7 @@ where
     T: StaticType,
 {
     fn static_type() -> Type {
-        Type::make_optional_type(T::static_type())
+        TyKind::Optional(T::static_type()).into()
     }
 }
 
@@ -83,7 +86,7 @@ where
     T: StaticType,
 {
     fn static_type() -> Type {
-        Type::make_list_type(T::static_type())
+        TyKind::List(T::static_type()).into()
     }
 }
 
diff --git a/serde_dhall/src/value.rs b/serde_dhall/src/value.rs
index a24f211..62632e5 100644
--- a/serde_dhall/src/value.rs
+++ b/serde_dhall/src/value.rs
@@ -1,11 +1,11 @@
-use dhall::semantics::Hir;
+use dhall::semantics::{Hir, Nir};
 use dhall::syntax::Expr;
-use dhall::{Normalized, Parsed};
+use dhall::Parsed;
 
-use crate::simple::{SimpleType, SimpleValue};
+use crate::simple::{Type as SimpleType, Value as SimpleValue};
 use crate::Error;
 
-/// A Dhall value.
+/// An arbitrary Dhall value.
 #[derive(Debug, Clone)]
 pub struct Value {
     /// Invariant: in normal form
@@ -21,28 +21,27 @@ impl Value {
     /// annotation.
     pub fn from_str_with_annot(
         s: &str,
-        ty: Option<&Self>,
+        ty: Option<&SimpleType>,
     ) -> Result<Self, Error> {
         Self::from_str_with_annot_dhall_error(s, ty).map_err(Error::Dhall)
     }
-    fn from_normalized(x: &Normalized) -> Self {
+    fn from_nir(x: &Nir) -> Self {
         Value {
-            hir: x.to_hir(),
-            as_simple_val: SimpleValue::from_nir(x.as_nir()),
-            as_simple_ty: SimpleType::from_nir(x.as_nir()),
+            hir: x.to_hir_noenv(),
+            as_simple_val: SimpleValue::from_nir(x),
+            as_simple_ty: SimpleType::from_nir(x),
         }
     }
-
     fn from_str_with_annot_dhall_error(
         s: &str,
-        ty: Option<&Self>,
+        ty: Option<&SimpleType>,
     ) -> Result<Self, dhall::error::Error> {
         let resolved = Parsed::parse_str(s)?.resolve()?;
         let typed = match ty {
             None => resolved.typecheck()?,
-            Some(ty) => resolved.typecheck_with(&ty.hir)?,
+            Some(ty) => resolved.typecheck_with(&ty.to_value().hir)?,
         };
-        Ok(Self::from_normalized(&typed.normalize()))
+        Ok(Self::from_nir(typed.normalize().as_nir()))
     }
 
     /// Converts a Value into a SimpleValue.
@@ -55,7 +54,7 @@ impl Value {
     }
 
     /// Converts a value back to the corresponding AST expression.
-    pub fn to_expr(&self) -> Expr {
+    pub(crate) fn to_expr(&self) -> Expr {
         self.hir.to_expr(Default::default())
     }
 }