First draft of "classes".

ConfusedSky · Oct 2, 2017 · fba138b · fba138b
1 parent 370320a
commit fba138b
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Showing 20 changed files with 2,557 additions and 323 deletions.
diff --git a/book/classes.md b/book/classes.md
diff --git a/c/vm.c b/c/vm.c
@@ -60,7 +60,8 @@ static void runtimeError(const char* format, ...) {
 //> Closures not-yet
     ObjFunction* function = frame->closure->function;
 //< Closures not-yet
-    size_t instruction = frame->ip - function->chunk.code;
+    // -1 because the IP is sitting on the next instruction to be executed.
+    size_t instruction = frame->ip - function->chunk.code - 1;
     fprintf(stderr, "[line %d] in ", function->chunk.lines[instruction]);
     if (function->name == NULL) {
       fprintf(stderr, "script\n");

diff --git a/java/com/craftinginterpreters/lox/Interpreter.java b/java/com/craftinginterpreters/lox/Interpreter.java
@@ -387,15 +387,15 @@ public Object visitLogicalExpr(Expr.Logical expr) {
 //> Classes interpreter-visit-set
   @Override
   public Object visitSetExpr(Expr.Set expr) {
-    Object value = evaluate(expr.value);
     Object object = evaluate(expr.object);
 
-    if (object instanceof LoxInstance) {
-      ((LoxInstance)object).set(expr.name, value);
-      return value;
+    if (!(object instanceof LoxInstance)) {
+      throw new RuntimeError(expr.name, "Only instances have fields.");
     }
 
-    throw new RuntimeError(expr.name, "Only instances have fields.");
+    Object value = evaluate(expr.value);
+    ((LoxInstance)object).set(expr.name, value);
+    return value;
   }
 //< Classes interpreter-visit-set
 //> Inheritance not-yet

diff --git a/java/com/craftinginterpreters/lox/LoxFunction.java b/java/com/craftinginterpreters/lox/LoxFunction.java
@@ -26,18 +26,18 @@ class LoxFunction implements LoxCallable {
 //< closure-constructor
     this.declaration = declaration;
   }
-//> Classes bind-self
-  LoxFunction bind(LoxInstance self) {
+//> Classes bind-instance
+  LoxFunction bind(LoxInstance instance) {
     Environment environment = new Environment(closure);
-    environment.define("this", self);
-/* Classes bind-self < Classes lox-function-bind-with-initializer
+    environment.define("this", instance);
+/* Classes bind-instance < Classes lox-function-bind-with-initializer
     return new LoxFunction(declaration, environment);
 */
 //> lox-function-bind-with-initializer
     return new LoxFunction(declaration, environment, isInitializer);
 //< lox-function-bind-with-initializer
   }
-//< Classes bind-self
+//< Classes bind-instance
 //> function-to-string
   @Override
   public String toString() {
@@ -75,6 +75,7 @@ public Object call(Interpreter interpreter, List<Object> arguments) {
     }
 //< catch-return
 //> Classes return-this
+
     if (isInitializer) return closure.getAt(0, "this");
 //< Classes return-this
     return null;

diff --git a/java/com/craftinginterpreters/lox/LoxInstance.java b/java/com/craftinginterpreters/lox/LoxInstance.java
@@ -24,7 +24,7 @@ Object get(Token name) {
     if (method != null) return method;
 
 //< lox-instance-get-method
-    throw new RuntimeError(name,
+    throw new RuntimeError(name, // [hidden]
         "Undefined property '" + name.lexeme + "'.");
   }
 //< lox-instance-get-property

diff --git a/java/com/craftinginterpreters/lox/Parser.java b/java/com/craftinginterpreters/lox/Parser.java
@@ -87,9 +87,9 @@ private Stmt classDeclaration() {
     }
 //< Inheritance not-yet
 
-    List<Stmt.Function> methods = new ArrayList<>();
     consume(LEFT_BRACE, "Expect '{' before class body.");
 
+    List<Stmt.Function> methods = new ArrayList<>();
     while (!check(RIGHT_BRACE) && !isAtEnd()) {
       methods.add(function("method"));
     }

diff --git a/java/com/craftinginterpreters/lox/Resolver.java b/java/com/craftinginterpreters/lox/Resolver.java
@@ -85,25 +85,26 @@ public Void visitClassStmt(Stmt.Class stmt) {
 //< Inheritance not-yet
 //> resolve-methods
 
-    for (Stmt.Function method : stmt.methods) {
 //> resolver-begin-this-scope
-      beginScope();
-      scopes.peek().put("this", true);
+    beginScope();
+    scopes.peek().put("this", true);
 
 //< resolver-begin-this-scope
-      FunctionType declaration = FunctionType.METHOD;
+    for (Stmt.Function method : stmt.methods) {
+      FunctionType declaration = FunctionType.METHOD; // [local]
 //> resolver-initializer-type
       if (method.name.lexeme.equals("init")) {
         declaration = FunctionType.INITIALIZER;
       }
 
 //< resolver-initializer-type
       resolveFunction(method, declaration);
-//> resolver-end-this-scope
-      endScope();
-//< resolver-end-this-scope
     }
 
+//> resolver-end-this-scope
+    endScope();
+
+//< resolver-end-this-scope
 //< resolve-methods
 //> Inheritance not-yet
     if (currentClass == ClassType.SUBCLASS) endScope();

diff --git a/note/log.txt b/note/log.txt
@@ -1,3 +1,16 @@
+2017/10/02 - 897 words, design note for "classes", finish first draft
+2017/10/01 - work on challenges for "classes"
+2017/09/30 - 179 words, outline design note for "classes"
+2017/09/29 - 2155 words across two sessions, first draft "classes"
+2017/09/28 - 828 words, first draft "classes"
+2017/09/27 - 835 words, first draft "classes"
+2017/09/26 - broke the chain, busy in aarhus and forgot :(
+             made up on 09/29
+2017/09/25 - 417 words, first draft "classes"
+2017/09/24 - 712 words, first draft "classes"
+2017/09/23 - 891 words, first draft "classes"
+2017/09/22 - 344 words, first draft "classes"
+2017/09/21 - 327 words, first draft "classes"
 2017/09/20 - finish rough outline "classes"
 2017/09/19 - 773 words outline "classes"
 2017/09/18 - 278 words outline "classes"