public object VisitAssignExpr(Expr.Assign expr)
{
object value = Evaluate(expr.value);
if (locals.TryGetValue(expr, out int distance))
{
environment.AssignAt(distance, expr.name, value);
}
else
{
globals.Assign(expr.name, value);
}
return(value);
}
public void Assign(Token name, Object value)
{
if (values.ContainsKey(name.lexeme))
{
values[name.lexeme] = value;
return;
}
if (enclosing != null)
{
enclosing.Assign(name, value);
return;
}
throw new RuntimeError(name, $"Undefined variable'{name.lexeme}'.");
}
public MyVoid VisitClassStmt(Stmt.Class stmt)
{
environment.Define(stmt.name.lexeme, null);
Dictionary <string, LoxFunction> methods = new Dictionary <string, LoxFunction>();
foreach (Stmt.Function method in stmt.methods)
{
LoxFunction function = new LoxFunction(method, environment, isInitializer: method.name.lexeme == "init");
methods[method.name.lexeme] = function;
}
LoxClass klass = new LoxClass(stmt.name.lexeme, methods);
environment.Assign(stmt.name, new LoxClass(stmt.name.lexeme, methods));
return(null);
}