Reorganized File Structure

Added Documentation

MathKit/MPToken.h

@@ -0,0 +1,160 @@
+//
+//  MPToken.h
+//  MathPad
+//
+//  Created by Kim Wittenburg on 19.09.14.
+//  Copyright (c) 2014 Kim Wittenburg. All rights reserved.
+//
+
+
+
+@class MPToken;
+@protocol MPToken;
+
+
+/*!
+    @typedef    MPTokenType
+    @brief      The type of a <code>token</code> identifies its behaviour in a mathematical
+                context.
+ 
+    @constant   MPEOFToken
+                A token that represents the end of the input. This token should
+                not be used to create a @c MPToken instance. It exists so that
+                you can safely send a @c tokenType message to @c nil without
+                getting confusing results. A token with this token type should be
+                interpreted as 'no token'.
+ 
+    @constant   MPMultiplicationSymbolToken
+                A multiplication symbol.
+ 
+    @constant   MPOperatorListToken
+                A list of operators (+ and - symbols). The token may be longer
+                than the number of operators if there are spaces between them.
+
+    @constant   MPElementaryFunction
+                @em Most elementary functions are represented by this token type.
+                Elementary functions not categorized as such are those that can
+                not be represented as text (e.g. roots and powers).
+ 
+    @constant   MPNumberToken
+                A number. This may be an integer or a floating point number.
+                Floating point numbers contain a @c NSLocaleDecimalSeparator.
+ 
+    @constant   MPVariableToken
+                A variable. A variable is exactly one character long.
+ 
+    @constant   MPFactorialToken
+                The factorial symbol (!).
+ 
+    @constant   MPEqualsToken
+                The equals sign.
+ 
+    @constant   MPGenericFunctionToken
+                A function represented by the @c MPFunction class. A token with
+                this token type is guaranteed to be a @c MPFunction instance.
+ 
+    @constant   MPWhitespaceToken
+                A whitespace. This token can typically be ignored.
+
+    @constant   MPUnidentifiedToken
+                Any symbol that does not match any other token.
+ */
+typedef NS_ENUM(NSUInteger, MPTokenType) {
+    MPEOFToken = 0,
+    MPMultiplicationSymbolToken,
+    MPOperatorListToken,
+    MPElementaryFunctionToken,
+    MPNumberToken,
+    MPDeformedNumberToken,
+    MPVariableToken,
+    MPEqualsToken,
+    MPFactorialToken,
+    MPPowerToken,
+    MPGenericFunctionToken,
+    
+    MPWhitespaceToken,
+    MPUnidentifiedToken,
+};
+
+
+
+/*!
+    @protocol   MPToken
+    @brief      Tokens represent logical units in an expresion.
+ */
+@protocol MPToken <NSObject>
+
+
+/*!
+    @method     tokenType
+    @brief      Returns the receiver's token type.
+ 
+    @discussion The token type identifies what kind of token the receiver is. For
+                more information see the documentation on the <code>MPTokenType
+                </code> enum.
+ 
+    @return     The receiver's token type.
+ */
+- (MPTokenType)tokenType;
+
+
+/*!
+    @method     range
+    @brief      Returns the receiver's range.
+ 
+    @discussion The range identifies where the token is in the expression. It is
+                specified in the symbol reference frame.
+ 
+    @return     The range the token occupies in the expression it was parsed
+                from specified in the symbol reference frame.
+ */
+- (NSRange)range;
+
+
+/*!
+    @method     stringValue
+    @brief      The string that caused the token to be parsed.
+ 
+    @discussion Depending on the type of the token the string value can have a
+                fixed or variable length. For example the equals token always has
+                a length of @c 1 whereas a number or whitespace token can be much
+                longer.
+ 
+    @return     The receiver's string value.
+ */
+- (NSString *)stringValue;
+
+@end
+
+
+
+/*!
+    @class      MPToken
+    @brief      The @c MPToken class implements the functionality of the @c
+                MPToken protocol. Most tokens are instances of the @c MPToken
+                class.
+ */
+@interface MPToken : NSObject <MPToken>
+
+
+/*!
+    @method     initWithTokenType:range:stringValue:
+    @brief      Creates a new @c MPToken instance.
+ 
+    @param      tokenType
+                The type of the token.
+ 
+    @param      range
+                The range of the token in the expression. Specified in the symbol
+                reference frame.
+ 
+    @param      input
+                The string value of the token.
+ 
+    @return     A newly initialized token.
+ */
+- (instancetype)initWithTokenType:(MPTokenType)tokenType
+                            range:(NSRange)range
+                      stringValue:(NSString *)input; /* designated initializer */
+
+@end