Decouple type checking info from CST and refactor checker.ts a bit

README.md

@@ -23,6 +23,22 @@ nice goodies, including:
  - **Cross-platform standard library**, allowing you to write your code for the
    web and the desktop at the same time.
 
+## Examples
+
+_Note that these examples are stil in the design phase and not able to compile._
+
+```ocaml
+import "html" ( HtmlComponent )
+
+let app : HtmlComponent.
+
+  let { fullname, .. } = perform get_app_state
+
+  return match user.
+    None => h1 [ "Please log in." ]
+    Some({ fullname, .. }) =>
+```
+
 ## Core Principles
 
 Bolt has a few fundamental design principles that we hope in time will make it

compiler/src/cst.ts

@@ -4,7 +4,7 @@ import path from "path"
 
 import { assert, implementationLimitation, IndentWriter, JSONObject, JSONValue, nonenumerable, unreachable } from "./util";
 import { isNodeWithScope, Scope } from "./scope"
-import type { InferContext, Kind, KindEnv, Scheme, TypeEnv } from "./checker"
+import type { Kind, Scheme } from "./checker"
 import type { Type } from "./types";
 import { Emitter } from "./emitter";
 
@@ -253,11 +253,6 @@ abstract class SyntaxBase {
   @nonenumerable
   public parent: Syntax | null = null;
 
-  @nonenumerable
-  public inferredKind?: Kind;
-  @nonenumerable
-  public inferredType?: Type;
-
   public abstract getFirstToken(): Token;
 
   public abstract getLastToken(): Token;
@@ -296,6 +291,10 @@ abstract class SyntaxBase {
     throw new Error(`Could not find a scope for ${this}. Maybe the parent links are not set?`);
   }
 
+  public getParentScope(): Scope | null {
+    return this.parent === null ? null : this.parent.getScope();
+  }
+
   public getEnclosingModule(): ModuleDeclaration | SourceFile {
     let curr = this.parent!;
     while (curr !== null) {
@@ -2595,9 +2594,6 @@ export class EnumDeclaration extends SyntaxBase {
 
   public readonly kind = SyntaxKind.EnumDeclaration;
 
-  @nonenumerable
-  public typeEnv?: TypeEnv;
-
   public constructor(
     public pubKeyword: PubKeyword | null,
     public enumKeyword: EnumKeyword,
@@ -2668,9 +2664,6 @@ export class StructDeclaration extends SyntaxBase {
 
   public readonly kind = SyntaxKind.StructDeclaration;
 
-  @nonenumerable
-  public typeEnv?: TypeEnv;
-
   public constructor(
     public pubKeyword: PubKeyword | null,
     public structKeyword: StructKeyword,
@@ -2836,9 +2829,6 @@ export class TypeDeclaration extends SyntaxBase {
 
   public readonly kind = SyntaxKind.TypeDeclaration;
 
-  @nonenumerable
-  public typeEnv?: TypeEnv;
-
   public constructor(
     public pubKeyword: PubKeyword | null,
     public typeKeyword: TypeKeyword,
@@ -2881,17 +2871,11 @@ export class LetDeclaration extends SyntaxBase {
   @nonenumerable
   public scope?: Scope;
 
-  @nonenumerable
-  public typeEnv?: TypeEnv;
-
   @nonenumerable
   public activeCycle?: boolean;
   @nonenumerable
   public visited?: boolean;
 
-  @nonenumerable
-  public context?: InferContext;
-
   public constructor(
     public pubKeyword: PubKeyword | null,
     public letKeyword: LetKeyword,
@@ -3082,9 +3066,6 @@ export class ClassDeclaration extends SyntaxBase {
 
   public readonly kind = SyntaxKind.ClassDeclaration;
 
-  @nonenumerable
-  public typeEnv?: TypeEnv;
-
   public constructor(
     public pubKeyword: PubKeyword | null,
     public classKeyword: ClassKeyword,
@@ -3186,9 +3167,6 @@ export class InstanceDeclaration extends SyntaxBase {
 
   public readonly kind = SyntaxKind.InstanceDeclaration;
 
-  @nonenumerable
-  public typeEnv?: TypeEnv;
-
   public constructor(
     public pubKeyword: PubKeyword | null,
     public classKeyword: InstanceKeyword,
@@ -3233,11 +3211,6 @@ export class ModuleDeclaration extends SyntaxBase {
 
   public readonly kind = SyntaxKind.ModuleDeclaration;
 
-  @nonenumerable
-  public typeEnv?: TypeEnv;
-  @nonenumerable
-  public kindEnv?: KindEnv;
-
   public constructor(
     public pubKeyword: PubKeyword | null,
     public modKeyword: ModKeyword,
@@ -3287,10 +3260,6 @@ export class SourceFile extends SyntaxBase {
 
   @nonenumerable
   public scope?: Scope;
-  @nonenumerable
-  public typeEnv?: TypeEnv;
-  @nonenumerable
-  public kindEnv?: KindEnv;
 
   public constructor(
     private file: TextFile,

compiler/src/types.ts

@@ -50,7 +50,7 @@ export abstract class TypeBase {
     this.find().parent = newType;
   }
 
-  public hasTypeVar(tv: TUniVar): boolean {
+  public hasTypeVar(tv: TRegularVar): boolean {
     for (const other of this.getTypeVars()) {
       if (tv.id === other.id) {
         return true;
@@ -105,7 +105,7 @@ export class TRigidVar extends TypeBase {
 
 }
 
-export class TUniVar extends TypeBase {
+export class TRegularVar extends TypeBase {
 
   public readonly kind = TypeKind.UniVar;
 
@@ -122,8 +122,8 @@ export class TUniVar extends TypeBase {
     yield this;
   }
 
-  public shallowClone(): TUniVar {
-    return new TUniVar(this.id, this.node);
+  public shallowClone(): TRegularVar {
+    return new TRegularVar(this.id, this.node);
   }
 
   public substitute(sub: TVSub): Type {
@@ -451,7 +451,7 @@ export type Type
   = TCon
   | TArrow
   | TRigidVar
-  | TUniVar
+  | TRegularVar
   | TApp
   | TField
   | TNil
@@ -459,10 +459,9 @@ export type Type
   | TAbsent
 
 export type TVar
-  = TUniVar
+  = TRegularVar
   | TRigidVar
 
-
 export function typesEqual(a: Type, b: Type): boolean {
   if (a.kind !== b.kind) {
     return false;