perf: Add benchmark and speedup

.eslintrc.cjs

@@ -79,6 +79,7 @@ module.exports = {
 			rules: {
 				// These off-by-default rules work well for this repo and we like them on.
 				"@typescript-eslint/no-confusing-void-expression": "off",
+				// "@typescript-eslint/switch-exhaustiveness-check": "error",
 				"deprecation/deprecation": "error",
 				"prefer-const": "off",
 			},

baselines/chapter12/attach-func-to-class.txt

@@ -0,0 +1 @@
+called function with argument

baselines/chapter12/call-detached-method.txt

@@ -0,0 +1 @@
+Jane

baselines/chapter12/crunch-bacon.txt

@@ -0,0 +1 @@
+Crunch crunch crunch!

baselines/chapter12/egotist.txt

@@ -0,0 +1 @@
+Egotist instance

baselines/chapter12/failed-method-lookup.errors.txt

@@ -0,0 +1,2 @@
+Undefined property meth.
+[line 3]

baselines/chapter12/failed-property-lookup.errors.txt

@@ -0,0 +1,2 @@
+Undefined property prop.
+[line 3]

baselines/chapter12/get-non-instance.errors.txt

@@ -0,0 +1,2 @@
+Only instances have properties.
+[line 2]

baselines/chapter12/invoke-init-directly.txt

@@ -0,0 +1,3 @@
+Foo instance
+Foo instance
+Foo instance

baselines/chapter12/linked-list.txt

@@ -0,0 +1,2 @@
+Cons instance
+3

baselines/chapter12/pathological-detachment.txt

@@ -0,0 +1 @@
+Jane

baselines/chapter12/print-instance.txt

@@ -0,0 +1,2 @@
+Bagel instance
+Bagel

baselines/chapter12/print-this-callback.txt

@@ -0,0 +1 @@
+Thing instance

baselines/chapter12/return-value-from-init.errors.txt

@@ -0,0 +1 @@
+[line 3] Error at 'return': Can't return a value from an initializer.

baselines/chapter12/set-non-instance.errors.txt

@@ -0,0 +1,2 @@
+Only instances have fields.
+[line 2]

baselines/chapter12/tasty-cake.txt

@@ -0,0 +1 @@
+The German chocolate cake is delicious!

baselines/chapter12/this-in-function.errors.txt

@@ -0,0 +1 @@
+[line 1] Error at 'this': Can't use 'this' outside of a class.

baselines/chapter12/this-outside-method.errors.txt

@@ -0,0 +1 @@
+[line 1] Error at 'this': Can't use 'this' outside of a class.

bench/fib.lox

@@ -0,0 +1,9 @@
+fun fib(n) {
+  if (n < 2) return n;
+  return fib(n - 1) + fib(n - 2); 
+}
+
+var before = clock();
+print fib(40);
+var after = clock();
+print after - before;

bench/fib33.lox

@@ -0,0 +1,10 @@
+fun fib(n) {
+  if (n < 2) return n;
+  return fib(n - 1) + fib(n - 2);
+}
+
+var before = clock();
+print fib(33);
+var after = clock();
+print "Time elapsed (ms):";
+print after - before;

cspell.json

@@ -29,6 +29,7 @@
 		"autofix",
 		"quickfix",
 		"Nystrom",
-		"unshadow"
+		"unshadow",
+		"klass"
 	]
 }

examples/chapter12/attach-func-to-class.lox

@@ -0,0 +1,9 @@
+class Box {}
+
+fun notMethod(argument) {
+  print "called function with " + argument;
+}
+
+var box = Box();
+box.function = notMethod;
+box.function("argument");  // should print argument

examples/chapter12/call-detached-method.lox

@@ -0,0 +1,11 @@
+class Person {
+  sayName() {
+    print this.name;
+  }
+}
+
+var jane = Person();
+jane.name = "Jane";
+
+var method = jane.sayName;
+method(); // should say "Jane"

examples/chapter12/crunch-bacon.lox

@@ -0,0 +1,7 @@
+class Bacon {
+  eat() {
+    print "Crunch crunch crunch!";
+  }
+}
+
+Bacon().eat(); // Prints "Crunch crunch crunch!".

examples/chapter12/egotist.lox

@@ -0,0 +1,8 @@
+class Egotist {
+  speak() {
+    print this;
+  }
+}
+
+var method = Egotist().speak;
+method();

examples/chapter12/failed-method-lookup.lox

@@ -0,0 +1,3 @@
+class Empty {}
+var e = Empty();
+print e.meth();

examples/chapter12/failed-property-lookup.lox

@@ -0,0 +1,3 @@
+class Empty {}
+var e = Empty();
+print e.prop;

examples/chapter12/get-non-instance.lox

@@ -0,0 +1,2 @@
+var x = 123;
+print x.length;

examples/chapter12/invoke-init-directly.lox

@@ -0,0 +1,8 @@
+class Foo {
+  init() {
+    print this;
+  }
+}
+
+var foo = Foo();
+print foo.init();

examples/chapter12/linked-list.lox

@@ -0,0 +1,17 @@
+class Cons {
+    init(head, tail) {
+        this.head = head;
+        this.tail = tail;
+    }
+
+    length() {
+        if (this.tail) {
+            return 1 + this.tail.length();
+        }
+        return 1;
+    }
+}
+
+var abc = Cons("a", Cons("b", Cons("c", nil)));
+print abc;
+print abc.length();

examples/chapter12/pathological-detachment.lox

@@ -0,0 +1,14 @@
+class Person {
+  sayName() {
+    print this.name;
+  }
+}
+
+var jane = Person();
+jane.name = "Jane";
+
+var bill = Person();
+bill.name = "Bill";
+
+bill.sayName = jane.sayName;
+bill.sayName(); // should say Jane

examples/chapter12/print-instance.lox

@@ -0,0 +1,4 @@
+class Bagel {}
+var bagel = Bagel();
+print bagel; // Prints "Bagel instance".
+print Bagel; // Prints "Bagel"

examples/chapter12/print-this-callback.lox

@@ -0,0 +1,12 @@
+class Thing {
+  getCallback() {
+    fun localFunction() {
+      print this;
+    }
+
+    return localFunction;
+  }
+}
+
+var callback = Thing().getCallback();
+callback();

examples/chapter12/return-value-from-init.lox

@@ -0,0 +1,5 @@
+class Foo {
+  init() {
+    return "something else";
+  }
+}

examples/chapter12/return-void-from-init.lox

@@ -0,0 +1,5 @@
+class Foo {
+  init() {
+    return;
+  }
+}

examples/chapter12/set-non-instance.lox

@@ -0,0 +1,2 @@
+var x = 123;
+x.base = 16;

examples/chapter12/tasty-cake.lox

@@ -0,0 +1,10 @@
+class Cake {
+  taste() {
+    var adjective = "delicious";
+    print "The " + this.flavor + " cake is " + adjective + "!";
+  }
+}
+
+var cake = Cake();
+cake.flavor = "German chocolate";
+cake.taste(); // Prints "The German chocolate cake is delicious!".

examples/chapter12/this-in-function.lox

@@ -0,0 +1 @@
+print this;

examples/chapter12/this-outside-method.lox

@@ -0,0 +1 @@
+print this;

package.json

@@ -20,6 +20,7 @@
 		"README.md"
 	],
 	"scripts": {
+		"benchmark": "pnpm --silent run repl bench/fib33.lox",
 		"build": "tsup",
 		"coverage": "pnpm test -- --coverage --no-watch",
 		"format": "prettier \"**/*\" --ignore-unknown",

src/ast-printer.ts

@@ -16,13 +16,15 @@ export const astPrinter: ExpressionVisitor<string> & StmtVisitor<string> = {
 			...block.statements.map((stmt) => visitStmt(stmt, astPrinter)),
 		),
 	call: (expr) => parenthesize(expr.callee, ...expr.args),
+	class: (stmt) => parenthesizeText("class", stmt.name.lexeme, "..."),
 	expr: (stmt) => visitExpr(stmt.expression, astPrinter),
 	func: (stmt) =>
 		parenthesizeText(
 			"func",
 			parenthesizeText(stmt.name.lexeme, ...stmt.params.map((p) => p.lexeme)),
 			visitStmt({ kind: "block", statements: stmt.body }, astPrinter),
 		),
+	get: (expr) => parenthesize("get", expr.object, expr.name.lexeme),
 	grouping: (expr) => parenthesize("group", expr.expr),
 	if: (stmt) =>
 		parenthesizeText(
@@ -35,6 +37,8 @@ export const astPrinter: ExpressionVisitor<string> & StmtVisitor<string> = {
 	logical: (expr) => parenthesize(expr.operator.lexeme, expr.left, expr.right),
 	print: (stmt) => parenthesize("print", stmt.expression),
 	return: (stmt) => parenthesize("return", ...(stmt.value ? [stmt.value] : [])),
+	set: (expr) => parenthesize("set", expr.object, expr.name.lexeme, expr.value),
+	this: () => parenthesize("this"),
 	unary: (expr) => parenthesize(expr.operator.lexeme, expr.right),
 	"var-expr": (expr) => String(expr.name.literal),
 	"var-stmt": (stmt) =>

src/ast.ts

@@ -43,6 +43,17 @@ export interface Call {
 	args: Expr[];
 }
 
+export interface Get {
+	kind: "get";
+	object: Expr;
+	name: Token;
+}
+
+export interface This {
+	kind: "this";
+	keyword: Token;
+}
+
 // Statements
 
 export interface Assign {
@@ -99,17 +110,34 @@ export interface Return {
 	value: Expr | null;
 }
 
+export interface Class {
+	kind: "class";
+	name: Token;
+	methods: Func[];
+}
+
+export interface SetExpr {
+	kind: "set";
+	object: Expr;
+	name: Token;
+	value: Expr;
+}
+
 export type Expr =
 	| Assign
 	| Binary
 	| Call
+	| Get
 	| Grouping
 	| Literal
 	| Logical
+	| SetExpr
+	| This
 	| Unary
 	| VarExpr;
 export type Stmt =
 	| Block
+	| Class
 	| Expression
 	| Func
 	| IfStmt
@@ -127,7 +155,8 @@ export type StmtVisitor<R> = {
 
 export function visitExpr<R>(expr: Expr, visitor: ExpressionVisitor<R>): R {
 	// XXX Can you model this without the "as never" in TS?
-	//     -> I think the answer is "yes if TS had dependent types"
+	// https://stackoverflow.com/q/77876338/388951
+	// https://github.com/microsoft/TypeScript/issues/30581
 	return visitor[expr.kind](expr as never);
 }