Added MPExpression and MPFunction Interfaces

MathPad/MPFunction.h

@@ -0,0 +1,47 @@
+//
+//  MPFunction.h
+//  MathPad
+//
+//  Created by Kim Wittenburg on 18.04.14.
+//  Copyright (c) 2014 Kim Wittenburg. All rights reserved.
+//
+
+@class MPFunction, MPExpression;
+
+@interface MPFunction : NSObject
+
+#pragma mark Creation Methods
+
+- (instancetype)init;
+
+#pragma mark Children
+
+- (NSUInteger)numberOfChildren;
+- (MPExpression *)childAtIndex;
+- (void)setChild:(MPExpression *)child atIndex:(NSUInteger)index;
+
+#pragma mark Evaluating Functions
+
+- (double)doubleValue;
+
+@end
+
+@interface MPFunction (MPFunctionExtensionMethods)
+
+#pragma mark Children
+
+- (NSArray *)children;
+
+#pragma mark Evaluating Expressions
+
+- (float)floatValue;
+- (int)intValue;
+- (NSInteger)integerValue;
+- (long long)longLongValue;
+- (NSString *)stringValue;
+
+- (NSString *)description;
+
+- (NSUInteger)hash;
+
+@end