internal LoxFunction bind(LoxInstance instance)
{
Envir envir = new Envir(Closure);
envir.define("this", instance);
return(new LoxFunction(Declaration, envir, IsInitializer));
}
public LoxFunction(Stmt.Function declaration, Envir closure,
bool isInitializer)
{
IsInitializer = isInitializer;
Closure = closure;
Declaration = declaration;
}
Envir ancestor(int distance)
{
Envir envir = this;
for (int i = 0; i < distance; i++)
{
envir = envir.Enclosing;
}
return(envir);
}
public void executeBlock(List <Stmt> statements, Envir envir)
{
Envir previous = env;
try {
env = envir;
foreach (var s in statements)
{
execute(s);
}
} finally {
env = previous;
}
}
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);
}
public object call(Interpreter interpreter, List <object> args)
{
Envir envir = new Envir(Closure);
for (int i = 0; i < Declaration.Parameters.Count; i++)
{
envir.define(Declaration.Parameters[i].Lexeme, args[i]);
}
try {
interpreter.executeBlock(Declaration.Body, envir);
} catch (LoxReturn returnValue) {
if (IsInitializer)
{
return(Closure.getAt(0, "this"));
}
return(returnValue.Value);
}
if (IsInitializer)
{
return(Closure.getAt(0, "this"));
}
return(null);
}
public Interpreter()
{
env = globals;
globals.define("clock", new Functions.ClockFunction());
}
public Envir()
{
Enclosing = null;
Values = new Dictionary <string, object>();
}
public Envir(Envir enclosing)
{
Enclosing = enclosing;
Values = new Dictionary <string, object>();
}