public LoxFunction Bind(LoxInstance instance)
{
Environment environment = new Environment(_closure);
environment.Define("this", instance);
return(new LoxFunction(_declaration, environment, _isInitializer));
}
public object Call(Interpreter interpreter, List <object> arguments)
{
Environment environment = new Environment(_closure);
for (int i = 0; i < _declaration.Parameter.Count; i++)
{
environment.Define(_declaration.Parameter[i].Lexeme, arguments[i]);
}
try
{
interpreter.ExecuteBlock(_declaration.Body, environment);
}
catch (Return returnValue)
{
if (_isInitializer)
{
return(_closure.GetAt(0, "this"));
}
return(returnValue.Value);
}
if (_isInitializer)
{
return(_closure.GetAt(0, "this"));
}
return(null);
}
internal Interpreter()
{
Globals = new Environment();
_environment = Globals;
Globals.Define("clock", new Globals.Clock() as ILoxCallable);
}
public LoxVoid VisitClassStmt(Stmt.Class stmt)
{
Option <LoxClass> superclassOption = stmt.Superclass.Match(
some: variableStmt =>
{
object superclassObj = Evalutate(variableStmt);
if (superclassObj is LoxClass superclass)
{
return(superclass.Some());
}
throw new RuntimeError(variableStmt.Name, "Superclass must be a class");
},
none: Option.None <LoxClass>
);
_environment.Define(stmt.Name.Lexeme, null);
superclassOption.MatchSome(super =>
{
_environment = new Environment(_environment);
_environment.Define("super", super);
});
Dictionary <string, LoxFunction> methods = stmt.Methods
.Select(method => (
name: method.Name.Lexeme,
method: new LoxFunction(method, _environment, method.Name.Lexeme == "init")
))
.ToDictionary(
x => x.name,
x => x.method
);
LoxClass @class = new LoxClass(stmt.Name.Lexeme, superclassOption, methods);
superclassOption.MatchSome(super =>
{
_environment = _environment.Enclosing.Match(
some: env => env,
none: () => throw new Exception("Expected enclosing scope none found")
);
});
_environment.Assign(stmt.Name, @class);
return(null);
}
internal void ExecuteBlock(List <Stmt> statments, Environment environment)
{
Environment previous = _environment;
try
{
_environment = environment;
foreach (Stmt statement in statments)
{
Execute(statement);
}
}
finally
{
this._environment = previous;
}
}
public LoxFunction(Stmt.Function declaration, Environment closure, bool isInitializer)
{
_closure = closure;
_declaration = declaration;
_isInitializer = isInitializer;
}
internal LoxLambda(Expr.Lambda declaration, Environment closure)
{
_closure = closure;
_declaration = declaration;
}