Xcode, deleted .pch file by mistake, can it be recovered?

Question

As i understand it, .pch files are responsible for precompiling header files. Sounds like something that can rebuilt or recreated.

2 questions:

1. Does Xcode have something similar to recycle bin from there file deletions can be undone?
2. Is there a direct way to rebuild .pch file?

Answer 1

The .pch file is generally very simple, and its contents depends upon the project type. The basic idea is that it includes the heavyweight header files. Xcode itself doesn't modify this file beyond the basic template; it'd only be different from the template if you changed it yourself.

For a Cocoa application, it is:

//
// Prefix header for all source files of the '%s' target in the '%s' project
//

#ifdef __OBJC__
    #import <Cocoa/Cocoa.h>
#endif

That's it! You can find all the templates in the SDK folder.

iOS: /Developer/Platforms/iPhoneOS.platform/Developer/Library/Xcode/Project Templates/

Answer 2

For CocoaTouch (iPhone) it's:

//
// Prefix header for all source files of the 'Test' target in the 'Test' project
//

#import <Availability.h>

#ifndef __IPHONE_3_0
#warning "This project uses features only available in iPhone SDK 3.0 and later."
#endif

#ifdef __OBJC__
#import <UIKit/UIKit.h>
#import <Foundation/Foundation.h>
#endif

Answer 3

if you deleted the pch header file, then pull it out of scm. if you don't use scm -- use scm (e.g. git).

if you're just referring to the precompiled result - xcode just rebuilds it as needed. it should never need to be rebuilt manually. if you actually need to rebuild it manually, you can locate it in your Derived Data directory (assuming Xc4), or simply clean the project and remove the precompiled headers during the clean. they will be automatically recreated on the next build.