diff --git a/MathPad/MPExpressionLayout.h b/MathPad/MPExpressionLayout.h
index decb929..7e9a8f9 100644
--- a/MathPad/MPExpressionLayout.h
+++ b/MathPad/MPExpressionLayout.h
@@ -9,10 +9,12 @@
 @import Cocoa;
 #import "MPLayout.h"
 #import "MPExpression.h"
+#import "MPFunctionLayout.h"
 
 @interface MPExpressionLayout : MPLayout
 
-- (instancetype)initRootLayoutWithExpression:(MPExpression *)expression;
+- (instancetype)initWithExpression:(MPExpression *)expression
+                            parent:(MPFunctionLayout *)parent;
 
 @property (readonly, nonatomic, weak) MPExpression *expression;
 
diff --git a/MathPad/MPExpressionLayout.m b/MathPad/MPExpressionLayout.m
index ccb008a..47a3220 100644
--- a/MathPad/MPExpressionLayout.m
+++ b/MathPad/MPExpressionLayout.m
@@ -41,36 +41,23 @@
 @implementation MPExpressionLayout
 
 # pragma mark Creation Methods
-- (instancetype)initRootLayoutWithExpression:(MPExpression *)expression
+- (instancetype)initWithExpression:(MPExpression *)expression
+                            parent:(MPFunctionLayout *)parent
 {
-    self = [super init];
+    self = [super initWithParent:parent];
     if (self) {
         _expression = expression;
     }
     return self;
 }
 
-- (instancetype)initWithElementAtPath:(NSIndexPath *)path
-                     inRootExpression:(MPExpression *)rootExpression
-                               parent:(MPLayout *)parent
-{
-    self = [super initWithElementAtPath:path
-                       inRootExpression:rootExpression
-                                 parent:parent];
-    if (self) {
-        _expression = [rootExpression elementAtIndexPath:path];
-    }
-    return self;
-}
-
 #pragma mark Cache Methods
 - (MPLayout *)childLayoutAtIndex:(NSUInteger)index
 {
     id cachedObject = [self cachableObjectForIndex:index generator:^id{
-        NSIndexPath *indexPath = [self.expression.indexPath indexPathByAddingIndex:index];
-        MPFunctionLayout *layout = [MPFunctionLayout functionLayoutForFunctionAtIndexPath:indexPath
-                                                                         inRootExpression:self.expression.rootExpression
-                                                                                   parent:self];
+        MPFunction *function = (MPFunction *)[self.expression elementAtIndex:index];
+        MPFunctionLayout *layout = [MPFunctionLayout functionLayoutForFunction:function
+                                                                        parent:self];
         layout.flipped = self.flipped;
         layout.usesSmallSize = self.usesSmallSize;
         return layout;
@@ -114,7 +101,7 @@
 - (NSRect)boundingRectForRange:(NSRange)range
 {
     NSUInteger startOffset;
-    NSUInteger startElementIndex = [self.expression indexOfElementAtSymbolLocation:range.location
+    NSUInteger startElementIndex = [self.expression indexOfElementAtLocation:range.location
                                                                            offset:&startOffset];
     // Calculate x position
     CGFloat x = 0, width = 0;
@@ -139,7 +126,7 @@
     }
 
     NSUInteger endOffset;
-    NSUInteger endElementIndex = [self.expression indexOfElementAtSymbolLocation:NSMaxRange(range)
+    NSUInteger endElementIndex = [self.expression indexOfElementAtLocation:NSMaxRange(range)
                                                                           offset:&endOffset];
 
     // Selection is inside of one string element
diff --git a/MathPad/MPExpressionStorage.m b/MathPad/MPExpressionStorage.m
index 0a771f5..872b8ff 100644
--- a/MathPad/MPExpressionStorage.m
+++ b/MathPad/MPExpressionStorage.m
@@ -24,7 +24,7 @@
 {
     self = [super initWithElements:elements];
     if (self) {
-        _rootLayout = [[MPExpressionLayout alloc] initRootLayoutWithExpression:self];
+        _rootLayout = [[MPExpressionLayout alloc] initWithExpression:self parent:nil];
     }
     return self;
 }
@@ -32,11 +32,11 @@
 - (void)setExpressionView:(MPExpressionView *)expressionView
 {
     _expressionView = expressionView;
-    self.rootLayout = [[MPExpressionLayout alloc] initRootLayoutWithExpression:self];
+    self.rootLayout = [[MPExpressionLayout alloc] initWithExpression:self parent:nil];
     self.rootLayout.flipped = expressionView.isFlipped;
 }
 
-- (void)didChangeElementsInRangePath:(MPRangePath *)rangePath
+- (void)didChangeElementsInIndexedRangePath:(MPRangePath *)rangePath
                    replacementLength:(NSUInteger)replacementLength
 {
     if (rangePath.location.length == 0) {
diff --git a/MathPad/MPExpressionView.h b/MathPad/MPExpressionView.h
index 3da1ec9..eb68fe0 100644
--- a/MathPad/MPExpressionView.h
+++ b/MathPad/MPExpressionView.h
@@ -22,7 +22,7 @@
 
 @property (readonly, nonatomic, strong) MPExpressionStorage *expressionStorage;
 
-@property (nonatomic, getter = isEditable) BOOL editable;
+// @property (nonatomic, getter = isEditable) BOOL editable;
 @property (nonatomic, strong) MPRangePath *selection;
 
 @property (nonatomic, weak) id target;
diff --git a/MathPad/MPExpressionView.m b/MathPad/MPExpressionView.m
index 79e2183..8390cee 100644
--- a/MathPad/MPExpressionView.m
+++ b/MathPad/MPExpressionView.m
@@ -112,7 +112,7 @@
     MPExpression *targetExpression = [self.expressionStorage elementAtIndexPath:targetExpressionPath];
     NSUInteger locationInTarget = selectionPath.lastIndex;
     NSUInteger locationInElement;
-    NSUInteger targetElementIndex = [targetExpression indexOfElementAtSymbolLocation:locationInTarget
+    NSUInteger targetElementIndex = [targetExpression indexOfElementAtLocation:locationInTarget
                                                                               offset:&locationInElement];
     
     id<MPExpressionElement> targetElement;
@@ -172,7 +172,7 @@
     MPExpression *targetExpression = [self.expressionStorage elementAtIndexPath:targetExpressionPath];
     NSUInteger locationInTarget = selectionPath.lastIndex;
     NSUInteger locationInElement;
-    NSUInteger targetElementIndex = [targetExpression indexOfElementAtSymbolLocation:locationInTarget
+    NSUInteger targetElementIndex = [targetExpression indexOfElementAtLocation:locationInTarget
                                                                               offset:&locationInElement];
     
     NSUInteger previousElementIndex = targetElementIndex - (locationInElement == 0 ? 1 : 0);
diff --git a/MathPad/MPFunctionLayout.h b/MathPad/MPFunctionLayout.h
index 61d9840..3768f59 100644
--- a/MathPad/MPFunctionLayout.h
+++ b/MathPad/MPFunctionLayout.h
@@ -11,9 +11,8 @@
 
 @interface MPFunctionLayout : MPLayout
 
-+ (MPFunctionLayout *)functionLayoutForFunctionAtIndexPath:(NSIndexPath *)path
-                                          inRootExpression:(MPExpression *)rootExpression
-                                                    parent:(MPExpressionLayout *)parent;
++ (MPFunctionLayout *)functionLayoutForFunction:(MPFunction *)function
+                                         parent:(MPExpressionLayout *)parent;
 
 @property (readonly, nonatomic, weak) MPFunction *function;
 
@@ -21,6 +20,9 @@
 
 @interface MPFunctionLayout (MPSubclassOverride)
 
+- (instancetype)initWithFunction:(MPFunction *)function
+                          parent:(MPExpressionLayout *)parent;
+
 #pragma mark Cache Methods
 - (CTLineRef)lineForPrivateCacheIndex:(NSUInteger)index
                             generator:(CTLineRef (^)())generator;
diff --git a/MathPad/MPFunctionLayout.m b/MathPad/MPFunctionLayout.m
index da17931..3484a26 100644
--- a/MathPad/MPFunctionLayout.m
+++ b/MathPad/MPFunctionLayout.m
@@ -16,31 +16,23 @@
 @implementation MPFunctionLayout
 
 #pragma mark Creation Methods
-+ (MPFunctionLayout *)functionLayoutForFunctionAtIndexPath:(NSIndexPath *)path
-                                          inRootExpression:(MPExpression *)rootExpression
-                                                    parent:(MPExpressionLayout *)parent
++ (MPFunctionLayout *)functionLayoutForFunction:(MPFunction *)function
+                                         parent:(MPExpressionLayout *)parent
 {
-    MPFunction *function = [rootExpression elementAtIndexPath:path];
     Class class = [function class];
     if (class == [MPSumFunction class]) {
-        return [[MPSumFunctionLayout alloc] initWithElementAtPath:path
-                                                 inRootExpression:rootExpression
-                                                           parent:parent];
+        return [[MPSumFunctionLayout alloc] initWithFunction:function parent:parent];
     }
-    return [[self alloc] initWithElementAtPath:path
-                              inRootExpression:rootExpression
-                                        parent:parent];
+    return [[self alloc] initWithFunction:function
+                                   parent:parent];
 }
 
-- (instancetype)initWithElementAtPath:(NSIndexPath *)path
-                     inRootExpression:(MPExpression *)rootExpression
-                               parent:(MPLayout *)parent
+- (instancetype)initWithFunction:(MPFunction *)function
+                          parent:(MPExpressionLayout *)parent
 {
-    self = [super initWithElementAtPath:path
-                       inRootExpression:rootExpression
-                                 parent:parent];
+    self = [super initWithParent:parent];
     if (self) {
-        _function = [rootExpression elementAtIndexPath:path];
+        _function = function;
     }
     return self;
 }
@@ -62,10 +54,9 @@
 - (MPLayout *)childLayoutAtIndex:(NSUInteger)index
 {
     return [self cachableObjectForIndex:index generator:^id{
-        NSIndexPath *childPath = [self.function.indexPath indexPathByAddingIndex:index];
-        MPExpressionLayout *layout = [[MPExpressionLayout alloc] initWithElementAtPath:childPath
-                                                                      inRootExpression:self.function.rootExpression
-                                                                                parent:self];
+        MPExpression *child = [self.function childAtIndex:index];
+        MPExpressionLayout *layout = [[MPExpressionLayout alloc] initWithExpression:child
+                                                                             parent:self];
         layout.flipped = self.flipped;
         layout.usesSmallSize = (index == 0 || index == 1) ? YES : self.usesSmallSize;
         return layout;
diff --git a/MathPad/MPLayout.h b/MathPad/MPLayout.h
index c211246..0eff489 100644
--- a/MathPad/MPLayout.h
+++ b/MathPad/MPLayout.h
@@ -15,9 +15,7 @@
 
 #pragma mark Creation Methods
 - (instancetype)init;
-- (instancetype)initWithElementAtPath:(NSIndexPath *)path
-                     inRootExpression:(MPExpression *)rootExpression
-                               parent:(MPLayout *)parent;
+- (instancetype)initWithParent:(MPLayout *)parent;
 
 #pragma mark Properties
 - (NSFont *)font;
diff --git a/MathPad/MPLayout.m b/MathPad/MPLayout.m
index a7e9492..3904f62 100644
--- a/MathPad/MPLayout.m
+++ b/MathPad/MPLayout.m
@@ -35,9 +35,7 @@
     return self;
 }
 
-- (instancetype)initWithElementAtPath:(NSIndexPath *)path
-                     inRootExpression:(MPExpression *)rootExpression
-                               parent:(MPLayout *)parent
+- (instancetype)initWithParent:(MPLayout *)parent
 {
     self = [self init];
     if (self) {