public object visitClassStmt(Stmt.Class stmt)
{
ClassType enclosingClass = currentClass;
currentClass = ClassType.CLASS;
declare(stmt.Name);
define(stmt.Name);
if (stmt.SuperClass != null &&
stmt.Name.Lexeme == stmt.SuperClass.Name.Lexeme)
{
Lox.error(stmt.SuperClass.Name,
"A class cannot inherit from itself");
}
if (stmt.SuperClass != null)
{
currentClass = ClassType.SUBCLASS;
resolve(stmt.SuperClass);
}
if (stmt.SuperClass != null)
{
beginScope();
scopes.Peek()["super"] = true;
}
beginScope();
scopes.Peek()["this"] = true;
foreach (Stmt.Function method in stmt.Methods)
{
FunctionType declaration = FunctionType.METHOD;
if (method.Name.Lexeme == "init")
{
declaration = FunctionType.INITIALIZER;
}
resolveFunction(method, declaration);
}
endScope();
if (stmt.SuperClass != null)
{
endScope();
}
currentClass = enclosingClass;
return(null);
}
public object visitClassStmt(Stmt.Class stmt)
{
object superClass = null;
if (stmt.SuperClass != null)
{
superClass = evaluate(stmt.SuperClass);
if (!(superClass is LoxClass))
{
throw new RuntimeError(stmt.SuperClass.Name,
"Superclass must be a class.");
}
}
env.define(stmt.Name.Lexeme, null);
if (stmt.SuperClass != null)
{
env = new Envir(env);
env.define("super", superClass);
}
Dictionary <string, LoxFunction> methods = new Dictionary <string, LoxFunction>();
foreach (Stmt.Function method in stmt.Methods)
{
LoxFunction function = new LoxFunction(method, env,
method.Name.Lexeme == "init");
methods[method.Name.Lexeme] = function;
}
LoxClass klass = new LoxClass(stmt.Name.Lexeme,
(LoxClass)superClass, methods);
if (stmt.SuperClass != null)
{
env = env.Enclosing;
}
env.assign(stmt.Name, klass);
return(null);
}