Add initial pretty printing for core types

Author: purefunctor

compiler-core/checking/src/check/kind.rs

@@ -32,7 +32,11 @@ pub fn infer_surface_kind<S: TypeStorage>(
             (t, k)
         }
 
-        lowering::TypeKind::Forall { .. } => default,
+        lowering::TypeKind::Forall { .. } => {
+            let t = convert::type_to_core(state, context, id);
+            let k = context.prim.t;
+            (t, k)
+        },
 
         lowering::TypeKind::Hole => default,
 

compiler-core/checking/src/core.rs

@@ -1,4 +1,5 @@
 pub mod debruijn;
+pub mod pretty;
 pub mod storage;
 
 pub use storage::TypeStorage;

compiler-core/checking/src/core/debruijn.rs

@@ -4,7 +4,7 @@
 //! and levels. The type checker uses a locally nameless representation
 //! for type variables, with additional abstractions for implicitly
 //! quantified type variables in permitted contexts like instance heads.
-use std::ops;
+use std::{fmt, ops};
 
 use lowering::{GraphNodeId, ImplicitBindingId, TypeVariableBindingId};
 use rustc_hash::FxHashMap;
@@ -39,6 +39,12 @@ pub struct Bound {
 #[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct Level(u32);
 
+impl fmt::Display for Level {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "&{}", self.0)
+    }
+}
+
 /// A De Bruijn index.
 ///
 /// De Bruijn indices are used to identify variables from the
@@ -52,6 +58,12 @@ pub struct Level(u32);
 #[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct Index(u32);
 
+impl fmt::Display for Index {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "*{}", self.0)
+    }
+}
+
 impl Bound {
     /// Returns the current De Bruijn [`Level`].
     pub fn level(&self) -> Level {

compiler-core/checking/src/lib.rs

@@ -5,13 +5,13 @@ use std::sync::Arc;
 
 use building_types::QueryResult;
 use files::FileId;
-use indexing::{IndexedModule, TermItemKind, TypeItemKind};
+use indexing::{IndexedModule, TypeItemKind};
 use lowering::LoweredModule;
 use resolving::ResolvedModule;
 
 use crate::{
-    check::{CheckContext, CheckState, PrimCore, convert, kind},
-    core::TypeStorage,
+    check::{CheckContext, CheckState, PrimCore, kind},
+    core::{TypeStorage, pretty::pretty_print},
 };
 
 pub trait External {
@@ -49,7 +49,13 @@ pub fn check_module(
             lowered.info.get_type_item(id)
         {
             let result = signature.map(|id| kind::infer_surface_kind(&mut state, &context, id));
-            dbg!(result);
+            if let Some((t, k)) = result {
+                println!(
+                    "{} :: {}",
+                    pretty_print(external, &state, &context, t),
+                    pretty_print(external, &state, &context, k)
+                )
+            }
         }
     }
 

tests-integration/src/lib.rs

@@ -101,7 +101,7 @@ test = 1 + 2 * 3 + 4
             r#"
 module Main where
 
-foreign import data Proxy :: Constraint
+foreign import data Proxy :: forall a b. a -> b -> a
 "#,
         );
 
@@ -132,6 +132,5 @@ foreign import data Proxy :: Constraint
 
         let mut storage = InlineStorage::default();
         checking::check_module(&mut engine, &mut storage, id).unwrap();
-        dbg!(storage);
     }
 }