Add skeleton implementation of storyboard.

Headers/AppKit/AppKit.h

@@ -225,6 +225,8 @@
 #import <AppKit/NSStepperTouchBarItem.h>
 #import <AppKit/NSStepper.h>
 #import <AppKit/NSStepperCell.h>
+#import <AppKit/NSStoryboard.h>
+#import <AppKit/NSStoryboardSegue.h>
 #import <AppKit/NSSwitch.h>
 #import <AppKit/NSTableColumn.h>
 #import <AppKit/NSTableHeaderCell.h>

Headers/AppKit/NSStoryboard.h

@@ -33,8 +33,28 @@
 extern "C" {
 #endif
 
+@class NSString, NSBundle;
+  
+typedef NSString *NSStoryboardName;
+typedef NSString *NSStoryboardSceneIdentifier;
+
+DEFINE_BLOCK_TYPE(NSStoryboardControllerCreator, NSCoder*, id);
+
 @interface NSStoryboard : NSObject
 
++ (NSStoryboard *) mainStoryboard; // 10.13
+  
++ (instancetype) storyboardWithName: (NSStoryboardName)name
+                             bundle: (NSBundle *)bundle;
+
+- (id) instantiateInitialController;
+
+- (id) instantiateInitialControllerWithCreator: (NSStoryboardControllerCreator)block; // 10.15
+
+- (id) instantiateControllerWithIdentifier: (NSStoryboardSceneIdentifier)identifier;
+
+- (id) instantiateControllerWithIdentifier: (NSStoryboardSceneIdentifier)identifier
+                                   creator: (NSStoryboardControllerCreator)block;  // 10.15
 @end
 
 #if	defined(__cplusplus)

Source/Functions.m

@@ -44,6 +44,7 @@
 #import "AppKit/NSView.h"
 #import "AppKit/NSWindow.h"
 #import "AppKit/DPSOperators.h"
+#import "AppKit/NSStoryboard.h"
 
 char **NSArgv = NULL;
 

Source/GNUmakefile

@@ -162,6 +162,8 @@ NSSharingServicePickerToolbarItem.m \
 NSSharingServicePickerTouchBarItem.m \
 NSSliderTouchBarItem.m \
 NSStepperTouchBarItem.m \
+NSStoryboard.m \
+NSStoryboardSegue.m \
 NSMagnificationGestureRecognizer.m \
 NSMatrix.m \
 NSMenu.m \
@@ -525,6 +527,8 @@ NSSplitView.h \
 NSStepper.h \
 NSStepperCell.h \
 NSStepperTouchBarItem.h \
+NSStoryboard.h \
+NSStoryboardSegue.h \
 NSStringDrawing.h \
 NSStatusBar.h \
 NSStatusItem.h \

Source/NSStoryboard.m

@@ -24,7 +24,40 @@
 
 #import <AppKit/NSStoryboard.h>
 
+static NSStoryboard *mainStoryboard = nil;
+
 @implementation NSStoryboard
 
++ (NSStoryboard *) mainStoryboard // 10.13
+{
+  return mainStoryboard;
+}
+
++ (instancetype) storyboardWithName: (NSStoryboardName)name
+                             bundle: (NSBundle *)bundle
+{
+  return nil;
+}
+
+- (id) instantiateInitialController
+{
+  return nil;
+}
+
+- (id) instantiateInitialControllerWithCreator: (NSStoryboardControllerCreator)block // 10.15
+{
+  return nil;
+}
+
+- (id) instantiateControllerWithIdentifier: (NSStoryboardSceneIdentifier)identifier
+{
+  return nil;
+}
+
+- (id) instantiateControllerWithIdentifier: (NSStoryboardSceneIdentifier)identifier
+                                   creator: (NSStoryboardControllerCreator)block  // 10.15
+{
+  return nil;
+}
 @end