Reorganized File Structure
Added Documentation
This commit is contained in:
Kim Wittenburg
816
MathKit/MPExpression.m
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816
MathKit/MPExpression.m
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//
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// MPExpression.m
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// MathPad
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//
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// Created by Kim Wittenburg on 10.08.14.
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// Copyright (c) 2014 Kim Wittenburg. All rights reserved.
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//
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#import "MPExpression.h"
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#import "MPExpressionElement.h"
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#import "MPFunction.h"
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#import "MPRangePath.h"
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#import "MPExpressionTokenizer.h"
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#import "MPToken.h"
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#import "MPExpressionParser.h"
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#import "MPParsedExpression.h"
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#import "NSIndexPath+MPAdditions.h"
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NSString *const MPIllegalElementException = @"Illegal Element Exception";
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NSString *const MPIllegalElementExceptionElementKey = @"MPIllegalElementExceptionElementKey";
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@interface MPExpression () {
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NSMutableArray * _elements;
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}
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/*!
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@method tokens
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@brief Private method. Returns an array containing all tokens from the
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receiver.
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@return All items in the <code>MPTokenReferenceFrame</code>.
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*/
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- (NSArray *)tokens;
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/*!
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@method validateElements:
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@brief Private method. Checks whether all objects in the specified array
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are valid expression elements.
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@discussion If an object is not valid a
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<code>MPIllegalElementException</code> is raised.
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@param elements
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The array of objects to be validated.
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*/
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- (void)validateElements:(NSArray *)elements;
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/*!
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@method fixElements
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@brief Private method. Restores consistency in the receiver after a
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change was made.
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*/
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- (void)fixElements;
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/*!
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@method _replaceSymbolsInRange:withElements:
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@brief Private method. Replaces the symbols in the specified range with
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the elements from the <code>elements</code> array.
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@discussion This is the most primitive mutation method of the @c MPExpression
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class.
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@param range
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The range of symbols to be replaced. The range is specified in
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the symbol reference frame. If the range exceeds the receiver's
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bounds a <code>NSRangeException</code> is raised.
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@param elements
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The elements that should replace the symbols in the specified
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range.
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*/
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- (void)_replaceSymbolsInRange:(NSRange)range
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withElements:(NSArray *)elements;
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/*!
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@method _splitElementsAtLocation:insertionIndex:
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@brief Splits the receiver's elements at the specified
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<code>location</code>.
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@discussion The split location can be inside a string element. In that case
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the string is replaced with two other smaller strings.
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Splitting the elements destroys the receiver's integrity. The
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receiver of this message must also receive a
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<code>-fixElements</code> message soon afterwards.
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@param location
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The index where to split the elements. Specified in the symbol
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reference frame.
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@param insertionIndex
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Splitting elements may shift the indexes of the following
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elements. This parameter is set to the index (specified in the
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element reference frame) that should be used to insert a new
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element at the location where the elements were previously
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splitted.
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@return @c YES if a string element was split into two smaller strings,
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<code>NO</code> if the split <code>location</code> corresponds to
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a location between two elements.
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*/
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- (BOOL)_splitElementsAtLocation:(NSUInteger)location
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insertionIndex:(NSUInteger *)insertionIndex;
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@end
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@implementation MPExpression {
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NSArray *_tokenCache;
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NSRange _editedRange;
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BOOL _didSplitStartOnEditing;
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BOOL _didSplitEndOnEditing;
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NSUInteger _replacementLength;
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}
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#pragma mark Creation Methods
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- (instancetype)init
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{
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return [self initWithElements:@[]];
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}
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- (instancetype)initWithElement:(id<MPExpressionElement>)element
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{
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return [self initWithElements:@[element]];
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}
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- (instancetype)initWithElements:(NSArray *)elements
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{
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self = [super init];
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if (self) {
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[self validateElements:elements];
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_elements = [[NSMutableArray alloc] initWithArray:elements
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copyItems:YES];
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[self fixElements];
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}
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return self;
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}
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#pragma mark Private Methods
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- (NSArray *)tokens
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{
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if (!_tokenCache) {
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_tokenCache = [MPExpressionTokenizer tokenizeExpression:self];
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}
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return _tokenCache;
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}
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- (void)validateElements:(NSArray *)elements
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{
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for (id element in elements) {
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if (![element conformsToProtocol:@protocol(MPExpressionElement)]) {
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@throw [NSException exceptionWithName:MPIllegalElementException
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reason:@"Elements must conform to the MPExpressionElement protocol."
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userInfo:@{MPIllegalElementExceptionElementKey: element}];
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}
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}
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}
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- (void)fixElements
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{
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for (NSUInteger index = 0; index < _elements.count; index++) {
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id<MPExpressionElement> next = index+1 < _elements.count ? _elements[index+1] : nil;
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id<MPExpressionElement> current = _elements[index];
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if ([current isString]) {
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if (current.length == 0) {
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[_elements removeObjectAtIndex:index];
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if (index >= _editedRange.location && index < NSMaxRange(_editedRange)) {
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--_replacementLength;
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}
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--index;
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} else if ([next isString]) {
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NSString *new = [NSString stringWithFormat:@"%@%@", current, next];
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[_elements replaceObjectsInRange:NSMakeRange(index, 2)
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withObjectsFromArray:@[new]];
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NSUInteger maxReplacementIndex = _editedRange.location + _replacementLength;
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if (index == _editedRange.location-1 && !_didSplitStartOnEditing) {
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--_editedRange.location;
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++_editedRange.length;
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if (index == maxReplacementIndex-1 && !_didSplitEndOnEditing) {
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++_editedRange.length;
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++_replacementLength;
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}
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} else if (index >= _editedRange.location && index < maxReplacementIndex - 1) {
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--_replacementLength;
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} else if (index == maxReplacementIndex-1 && !_didSplitEndOnEditing) {
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++_editedRange.length;
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}
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--index;
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}
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} else {
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[(MPFunction *)current setParent:self];
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}
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}
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}
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#pragma mark Querying Expressions
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- (MPExpression *)rootExpression
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{
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if (self.parent == nil) {
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return self;
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}
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return [self.parent rootExpression];
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}
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- (NSIndexPath *)indexPath
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{
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if (self.parent) {
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NSUInteger selfIndex = [self.parent indexOfChild:self];
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return [[self.parent indexPath] indexPathByAddingIndex:selfIndex];
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} else {
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return [[NSIndexPath alloc] init];
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}
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}
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- (NSUInteger)countItemsInReferenceFrame:(MPReferenceFrame)referenceFrame
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{
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switch (referenceFrame) {
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case MPElementReferenceFrame:
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return _elements.count;
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case MPSymbolReferenceFrame:
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{
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NSUInteger count = 0;
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for (id<MPExpressionElement> element in _elements) {
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count += element.length;
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}
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return count;
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}
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case MPTokenReferenceFrame:
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return self.tokens.count;
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}
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}
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- (id)itemAtIndex:(NSUInteger)anIndex
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referenceFrame:(MPReferenceFrame)referenceFrame
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{
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switch (referenceFrame) {
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case MPElementReferenceFrame:
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return _elements[anIndex];
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case MPSymbolReferenceFrame:
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{
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NSUInteger offsetInElement;
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NSUInteger elementIndex = [self convertIndex:anIndex
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fromReferenceFrame:MPSymbolReferenceFrame
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toReferenceFrame:MPElementReferenceFrame
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offset:&offsetInElement];
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id<MPExpressionElement> element = [self elementAtIndex:elementIndex];
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if ([element isFunction]) {
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return element;
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} else {
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return [((NSString *)element) substringWithRange:NSMakeRange(offsetInElement, 1)];
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}
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}
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case MPTokenReferenceFrame:
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return self.tokens[anIndex];
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}
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}
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- (id<MPExpressionElement>)elementAtIndex:(NSUInteger)anIndex
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referenceFrame:(MPReferenceFrame)referenceFrame
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{
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NSUInteger elementIndex = [self convertIndex:anIndex
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fromReferenceFrame:referenceFrame
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toReferenceFrame:MPElementReferenceFrame];
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return _elements[elementIndex];
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}
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#warning If multiple equal expressions exist errors may occur...
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- (NSUInteger)indexOfElement:(id<MPExpressionElement>)element
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{
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return [_elements indexOfObject:element];
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}
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- (NSArray *)itemsInRange:(NSRange)aRange
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referenceFrame:(MPReferenceFrame)referenceFrame
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{
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MPExpression *subexpression = [self subexpressionWithRange:aRange
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referenceFrame:referenceFrame];
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return [subexpression allItemsInReferenceFrame:referenceFrame];
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}
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- (NSArray *)allItemsInReferenceFrame:(MPReferenceFrame)referenceFrame
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{
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switch (referenceFrame) {
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case MPElementReferenceFrame:
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return _elements;
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case MPSymbolReferenceFrame:
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{
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NSMutableArray *symbols = [[NSMutableArray alloc] init];
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for (id<MPExpressionElement> element in _elements) {
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if ([element isString]) {
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for (NSUInteger i = 0; i < [element length]; i++) {
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NSString *ichar = [NSString stringWithFormat:@"%c", [((NSString *)element) characterAtIndex:i]];
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[symbols addObject:ichar];
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}
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} else {
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[symbols addObject:element];
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}
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}
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}
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case MPTokenReferenceFrame:
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return self.tokens;
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}
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}
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- (id)elementAtIndexPath:(NSIndexPath *)indexPath
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{
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if (indexPath.length == 0) {
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return self;
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}
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id<MPExpressionElement> element = _elements[[indexPath indexAtPosition:0]];
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if (indexPath.length == 1) {
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return element;
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}
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if ([element isFunction]) {
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return [(MPFunction *)element elementAtIndexPath:[indexPath indexPathByRemovingFirstIndex]];
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}
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// TODO: Raise appropriate exeption.
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return nil;
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}
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- (NSUInteger)convertIndex:(NSUInteger)anIndex
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fromReferenceFrame:(MPReferenceFrame)fromReferenceFrame
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toReferenceFrame:(MPReferenceFrame)toReferenceFrame
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{
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return [self convertIndex:anIndex
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fromReferenceFrame:fromReferenceFrame
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toReferenceFrame:toReferenceFrame
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offset:NULL];
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}
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- (NSUInteger)convertIndex:(NSUInteger)anIndex
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fromReferenceFrame:(MPReferenceFrame)fromReferenceFrame
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toReferenceFrame:(MPReferenceFrame)toReferenceFrame
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offset:(NSUInteger *)offset
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{
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if (fromReferenceFrame == toReferenceFrame || anIndex == 0) {
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if (offset) {
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*offset = 0;
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}
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return anIndex;
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}
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NSUInteger symbolIndex __block = 0;
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switch (fromReferenceFrame) {
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case MPElementReferenceFrame:
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[_elements enumerateObjectsUsingBlock:^(id<MPExpressionElement> obj, NSUInteger idx, BOOL *stop) {
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symbolIndex += obj.length;
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*stop = idx >= anIndex - 1;
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}];
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break;
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case MPSymbolReferenceFrame:
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symbolIndex = anIndex;
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break;
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case MPTokenReferenceFrame:
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[self.tokens enumerateObjectsUsingBlock:^(id<MPToken> obj, NSUInteger idx, BOOL *stop) {
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symbolIndex += obj.range.length;
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*stop = idx >= anIndex - 1;
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}];
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break;
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}
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switch (toReferenceFrame) {
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case MPElementReferenceFrame:
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{
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NSUInteger totalLength = 0;
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NSUInteger elementIndex = 0;
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id<MPExpressionElement> element;
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while (totalLength < symbolIndex) {
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element = _elements[elementIndex++];
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totalLength += element.length;
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}
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--elementIndex;
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NSUInteger offsetInElement = element.length - totalLength + symbolIndex;
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if (offsetInElement == element.length) {
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offsetInElement = 0;
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elementIndex++;
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}
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if (offset) {
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*offset = offsetInElement;
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}
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return elementIndex;
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}
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case MPSymbolReferenceFrame:
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if (offset) {
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*offset = 0;
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}
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return symbolIndex;
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case MPTokenReferenceFrame:
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{
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NSUInteger totalLength = 0;
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NSUInteger tokenIndex = 0;
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id<MPToken> token;
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while (totalLength < symbolIndex) {
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token = self.tokens[tokenIndex++];
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totalLength += token.range.length;
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}
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--tokenIndex;
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NSUInteger offsetInToken = token.range.length - totalLength + symbolIndex;
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if (offsetInToken == token.range.length) {
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offsetInToken = 0;
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tokenIndex++;
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}
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if (offset) {
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*offset = offsetInToken;
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}
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return tokenIndex;
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}
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}
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}
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- (NSRange)convertRange:(NSRange)aRange
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fromReferenceFrame:(MPReferenceFrame)fromReferenceFrame
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toReferenceFrame:(MPReferenceFrame)toReferenceFrame
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{
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return [self convertRange:aRange
|
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fromReferenceFrame:fromReferenceFrame
|
||||
toReferenceFrame:toReferenceFrame
|
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leadingOffset:NULL
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||||
trailingOffset:NULL];
|
||||
}
|
||||
|
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|
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- (NSRange)convertRange:(NSRange)aRange
|
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fromReferenceFrame:(MPReferenceFrame)fromReferenceFrame
|
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toReferenceFrame:(MPReferenceFrame)toReferenceFrame
|
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leadingOffset:(NSUInteger *)leadingOffset
|
||||
trailingOffset:(NSUInteger *)trailingOffset
|
||||
{
|
||||
NSUInteger start = [self convertIndex:aRange.location
|
||||
fromReferenceFrame:fromReferenceFrame
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toReferenceFrame:toReferenceFrame
|
||||
offset:leadingOffset];
|
||||
NSUInteger end = [self convertIndex:NSMaxRange(aRange)
|
||||
fromReferenceFrame:fromReferenceFrame
|
||||
toReferenceFrame:toReferenceFrame
|
||||
offset:trailingOffset];
|
||||
return NSMakeRange(start, end - start);
|
||||
}
|
||||
|
||||
|
||||
#pragma mark Mutating Expressions
|
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|
||||
|
||||
- (void)replaceItemsInRange:(NSRange)aRange
|
||||
referenceFrame:(MPReferenceFrame)referenceFrame
|
||||
withElements:(NSArray *)elements
|
||||
{
|
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NSUInteger start = [self convertIndex:aRange.location
|
||||
fromReferenceFrame:referenceFrame
|
||||
toReferenceFrame:MPSymbolReferenceFrame];
|
||||
NSUInteger end = [self convertIndex:NSMaxRange(aRange)
|
||||
fromReferenceFrame:referenceFrame
|
||||
toReferenceFrame:MPSymbolReferenceFrame];
|
||||
[self _replaceSymbolsInRange:NSMakeRange(start, end - start)
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withElements:elements];
|
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}
|
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|
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- (void)_replaceSymbolsInRange:(NSRange)range
|
||||
withElements:(NSArray *)elements
|
||||
{
|
||||
if (NSMaxRange(range) > [self countItemsInReferenceFrame:MPSymbolReferenceFrame]) {
|
||||
@throw [NSException exceptionWithName:NSRangeException
|
||||
reason:@"Range out of bounds of expression"
|
||||
userInfo:nil];
|
||||
}
|
||||
[self validateElements:elements];
|
||||
|
||||
// Locate the position, split the elements
|
||||
NSUInteger startIndex; // startIndex is inclusive
|
||||
BOOL didSplitStart = NO;
|
||||
if (_elements.count == 0) {
|
||||
startIndex = 0;
|
||||
} else {
|
||||
didSplitStart = [self _splitElementsAtLocation:range.location
|
||||
insertionIndex:&startIndex];
|
||||
}
|
||||
NSUInteger endIndex; // endIndex is exclusive
|
||||
BOOL didSplitEnd = [self _splitElementsAtLocation:NSMaxRange(range)
|
||||
insertionIndex:&endIndex];
|
||||
|
||||
// Perform the replacement
|
||||
NSMutableArray *newElements = [[NSMutableArray alloc] initWithArray:elements
|
||||
copyItems:YES];
|
||||
NSArray *removedElements = [_elements subarrayWithRange:NSMakeRange(startIndex, endIndex-startIndex)];
|
||||
[_elements replaceObjectsInRange:NSMakeRange(startIndex, endIndex-startIndex)
|
||||
withObjectsFromArray:newElements];
|
||||
for (id<MPExpressionElement> element in removedElements) {
|
||||
if ([element isFunction]) {
|
||||
((MPFunction *)element).parent = nil;
|
||||
}
|
||||
}
|
||||
|
||||
_tokenCache = nil;
|
||||
|
||||
NSUInteger editLocation = startIndex - (didSplitStart ? 1 : 0);
|
||||
NSUInteger editLength = endIndex - startIndex;
|
||||
if (range.length == 0 && didSplitStart) {
|
||||
editLength = 1;
|
||||
}
|
||||
|
||||
_editedRange = NSMakeRange(editLocation, editLength);
|
||||
_didSplitStartOnEditing = didSplitStart;
|
||||
_didSplitEndOnEditing = didSplitEnd;
|
||||
_replacementLength = elements.count;
|
||||
if (didSplitStart) {
|
||||
_replacementLength++;
|
||||
if (range.length == 0) {
|
||||
_replacementLength++;
|
||||
}
|
||||
}
|
||||
if (didSplitEnd) {
|
||||
_replacementLength++;
|
||||
}
|
||||
|
||||
[self fixElements];
|
||||
[self changedElementsInRangePath:[[MPRangePath alloc] initWithRange:_editedRange]
|
||||
replacementLength:_replacementLength];
|
||||
}
|
||||
|
||||
|
||||
- (BOOL)_splitElementsAtLocation:(NSUInteger)location
|
||||
insertionIndex:(NSUInteger *)insertionIndex
|
||||
{
|
||||
if (location == 0) {
|
||||
*insertionIndex = 0;
|
||||
return NO;
|
||||
}
|
||||
|
||||
NSUInteger splitOffset;
|
||||
NSUInteger splitElementIndex = [self convertIndex:location
|
||||
fromReferenceFrame:MPSymbolReferenceFrame
|
||||
toReferenceFrame:MPElementReferenceFrame
|
||||
offset:&splitOffset];
|
||||
if (splitOffset != 0) {
|
||||
NSString *splitElement = (NSString *)_elements[splitElementIndex];
|
||||
NSString *leftPart = [splitElement substringToIndex:splitOffset];
|
||||
NSString *rightPart = [splitElement substringFromIndex:splitOffset];
|
||||
[_elements replaceObjectsInRange:NSMakeRange(splitElementIndex, 1)
|
||||
withObjectsFromArray:@[leftPart, rightPart]];
|
||||
++splitElementIndex;
|
||||
}
|
||||
*insertionIndex = splitElementIndex;
|
||||
return splitOffset != 0;
|
||||
}
|
||||
|
||||
|
||||
- (void)changedElementsInRangePath:(MPRangePath *)rangePath
|
||||
replacementLength:(NSUInteger)replacementLength
|
||||
{
|
||||
NSUInteger selfIndex = [self.parent indexOfChild:self];
|
||||
MPRangePath *newPath = MPMakeRangePath([rangePath.location indexPathByPreceedingIndex:selfIndex], rangePath.length);
|
||||
[self.parent didChangeElementsInRangePath:newPath
|
||||
replacementLength:replacementLength];
|
||||
}
|
||||
|
||||
|
||||
- (MPExpression *)subexpressionFromIndex:(NSUInteger)from
|
||||
referenceFrame:(MPReferenceFrame)referenceFrame
|
||||
{
|
||||
return [self subexpressionWithRange:NSMakeRange(from, [self countItemsInReferenceFrame:referenceFrame] - from)
|
||||
referenceFrame:referenceFrame];
|
||||
}
|
||||
|
||||
|
||||
- (MPExpression *)subexpressionToIndex:(NSUInteger)to
|
||||
referenceFrame:(MPReferenceFrame)referenceFrame
|
||||
{
|
||||
return [self subexpressionWithRange:NSMakeRange(0, to)
|
||||
referenceFrame:referenceFrame];
|
||||
}
|
||||
|
||||
|
||||
- (MPExpression *)subexpressionWithRange:(NSRange)aRange
|
||||
referenceFrame:(MPReferenceFrame)referenceFrame
|
||||
{
|
||||
MPExpression *subexpression = [self copy];
|
||||
NSRange preceedingRange = NSMakeRange(0, aRange.location);
|
||||
NSUInteger firstOut = NSMaxRange(aRange);
|
||||
NSRange exceedingRange = NSMakeRange(firstOut, [self countItemsInReferenceFrame:referenceFrame] - firstOut);
|
||||
[subexpression deleteElementsInRange:exceedingRange
|
||||
referenceFrame:referenceFrame];
|
||||
[subexpression deleteElementsInRange:preceedingRange
|
||||
referenceFrame:referenceFrame];
|
||||
return subexpression;
|
||||
}
|
||||
|
||||
|
||||
#pragma mark Evaluating Expressions
|
||||
|
||||
|
||||
- (MPParsedExpression *)parse:(NSArray *__autoreleasing *)errors
|
||||
{
|
||||
return [self parseExpectingVariable:NO
|
||||
errors:errors];
|
||||
}
|
||||
|
||||
|
||||
- (MPParsedExpression *)parseExpectingVariable:(BOOL)flag
|
||||
errors:(NSArray *__autoreleasing *)errors
|
||||
{
|
||||
return [[[MPExpressionParser alloc] initWithExpression:self] parseExpectingVariableDefinition:flag
|
||||
errors:errors];
|
||||
}
|
||||
|
||||
|
||||
#pragma mark Basic NSObject Methods
|
||||
|
||||
|
||||
- (NSString *)description
|
||||
{
|
||||
#warning Bad Implementation
|
||||
NSMutableString *description = [[NSMutableString alloc] init];
|
||||
NSUInteger index = 0;
|
||||
for (id element in _elements) {
|
||||
if ([element isString]) {
|
||||
NSMutableString *correctedSymbol = [[element stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] mutableCopy];
|
||||
// Prefix operator
|
||||
if (element != _elements[0]) {
|
||||
unichar prefix = [correctedSymbol characterAtIndex:0];
|
||||
if ([[NSCharacterSet decimalDigitCharacterSet] characterIsMember:prefix]) {
|
||||
[correctedSymbol insertString:@"*"
|
||||
atIndex:0];
|
||||
}
|
||||
}
|
||||
// Suffix operator
|
||||
if (element != [_elements lastObject]) {
|
||||
unichar suffix = [correctedSymbol characterAtIndex:correctedSymbol.length-1];
|
||||
if ([[NSCharacterSet decimalDigitCharacterSet] characterIsMember:suffix]) {
|
||||
[correctedSymbol appendString:@"*"];
|
||||
}
|
||||
}
|
||||
[description appendString:correctedSymbol];
|
||||
} else if (index > 0 && [_elements[index-1] isKindOfClass:[MPFunction class]]) {
|
||||
[description appendFormat:@"*%@", [element description]];
|
||||
} else {
|
||||
[description appendString:[element description]];
|
||||
}
|
||||
index++;
|
||||
}
|
||||
return description;
|
||||
}
|
||||
|
||||
|
||||
- (NSUInteger)hash
|
||||
{
|
||||
return [_elements hash];
|
||||
}
|
||||
|
||||
|
||||
#pragma mark - NSCopying
|
||||
|
||||
|
||||
- (id)copyWithZone:(NSZone *)zone
|
||||
{
|
||||
MPExpression *copy = [[MPExpression allocWithZone:zone] initWithElements:_elements];
|
||||
return copy;
|
||||
}
|
||||
|
||||
|
||||
#pragma mark - NSCoding
|
||||
|
||||
|
||||
- (id)initWithCoder:(NSCoder *)aDecoder
|
||||
{
|
||||
// TODO: Test Coding
|
||||
return [self initWithElements:[aDecoder decodeObject]];
|
||||
}
|
||||
|
||||
|
||||
- (void)encodeWithCoder:(NSCoder *)aCoder
|
||||
{
|
||||
[aCoder encodeObject:_elements];
|
||||
}
|
||||
|
||||
@end
|
||||
|
||||
|
||||
|
||||
@implementation MPExpression (MPExpressionConvenience)
|
||||
|
||||
#pragma mark Querying Expressions
|
||||
|
||||
|
||||
- (NSUInteger)countElements
|
||||
{
|
||||
return [self countItemsInReferenceFrame:MPElementReferenceFrame];
|
||||
}
|
||||
|
||||
|
||||
- (NSUInteger)countSymbols
|
||||
{
|
||||
return [self countItemsInReferenceFrame:MPSymbolReferenceFrame];
|
||||
}
|
||||
|
||||
|
||||
- (NSUInteger)countTokens
|
||||
{
|
||||
return [self countItemsInReferenceFrame:MPTokenReferenceFrame];
|
||||
}
|
||||
|
||||
|
||||
- (id<MPExpressionElement>)elementAtIndex:(NSUInteger)anIndex
|
||||
{
|
||||
return [self itemAtIndex:anIndex
|
||||
referenceFrame:MPElementReferenceFrame];
|
||||
}
|
||||
|
||||
|
||||
- (id<MPExpressionElement>)symbolAtIndex:(NSUInteger)anIndex
|
||||
{
|
||||
return [self itemAtIndex:anIndex
|
||||
referenceFrame:MPSymbolReferenceFrame];
|
||||
}
|
||||
|
||||
|
||||
- (id<MPToken>)tokenAtIndex:(NSUInteger)anIndex
|
||||
{
|
||||
return [self itemAtIndex:anIndex
|
||||
referenceFrame:MPTokenReferenceFrame];
|
||||
}
|
||||
|
||||
|
||||
#pragma mark Mutating Expressions
|
||||
|
||||
|
||||
- (void)appendElement:(id<MPExpressionElement>)anElement
|
||||
{
|
||||
[self appendElements:@[anElement]];
|
||||
}
|
||||
|
||||
|
||||
- (void)appendElements:(NSArray *)elements
|
||||
{
|
||||
[self replaceItemsInRange:NSMakeRange([self countItemsInReferenceFrame:MPSymbolReferenceFrame], 0)
|
||||
referenceFrame:MPSymbolReferenceFrame
|
||||
withElements:elements];
|
||||
}
|
||||
|
||||
|
||||
- (void)insertElement:(id<MPExpressionElement>)anElement
|
||||
atIndex:(NSUInteger)index
|
||||
referenceFrame:(MPReferenceFrame)referenceFrame
|
||||
{
|
||||
[self insertElements:@[anElement]
|
||||
atIndex:index
|
||||
referenceFrame:referenceFrame];
|
||||
}
|
||||
|
||||
|
||||
- (void)insertElements:(NSArray *)elements
|
||||
atIndex:(NSUInteger)index
|
||||
referenceFrame:(MPReferenceFrame)referenceFrame
|
||||
{
|
||||
[self replaceItemsInRange:NSMakeRange(index, 0)
|
||||
referenceFrame:referenceFrame
|
||||
withElements:elements];
|
||||
}
|
||||
|
||||
|
||||
- (void)deleteElementsInRange:(NSRange)range
|
||||
referenceFrame:(MPReferenceFrame)referenceFrame
|
||||
{
|
||||
[self replaceItemsInRange:range
|
||||
referenceFrame:referenceFrame
|
||||
withElements:@[]];
|
||||
}
|
||||
|
||||
@end
|
||||
Reference in New Issue
Block a user