//
//  MPExpressionTreeElement.h
//  MathPad
//
//  Created by Kim Wittenburg on 09.10.14.
//  Copyright (c) 2014 Kim Wittenburg. All rights reserved.
//

@class MPTokenStream;

@protocol MPExpressionTreeElement <NSObject>
@required

- (instancetype)init;
- (instancetype)initWithTokenStream:(MPTokenStream *)tokenStream;

- (BOOL)validate:(NSError *__autoreleasing *)error;
- (NSDecimalNumber *)evaluate;

@end