//

//  MYCoroutine.h

//  Coroutines for Mac OS X

//

//  Created by Jens Alfke on 4/29/08.

//  Copyright 2008 Jens Alfke. All rights reserved.

//

#import <Foundation/Foundation.h>

/** Objective-C coroutine class.

    See: http://en.wikipedia.org/wiki/Coroutine 

*/

@interface MYCoroutine : NSObject

{

    @private

    struct CoroX *_coro;

    NSInvocation *_invocation;

    NSString *_name;

}

/** The "main" coroutine: the one corresponding to the execution context before the

    first coroutine is started. */

+ (MYCoroutine*) mainCoroutine;

/** The currently active coroutine. */

+ (MYCoroutine*) currentCoroutine;

/** Creates a new coroutine and starts it, performing the given invocation on it.

    That method must not return! */

+ (MYCoroutine*) startWithInvocation: (NSInvocation*)invocation;

/** Creates but does not start a coroutine. */

- (id) init;

@property (retain) NSInvocation *invocation;

/** The stack size of the coroutine. You can only change this before calling -start! */

@property size_t stackSize;

/** The coroutine's name. You can put anything you want here, as a debugging aid. */

@property (copy) NSString* name;

/** The "main" method that will be called if the coroutine is started with -start.

    The default implementation is empty, so a subclass using -start must override this. */

- (void) main;

/** Returns control to a coroutine.

    The most recent -resume call made from within that coroutine will return.

    The current coroutine will block (i.e. this call won't return)

    until some other coroutine tells it to resume. */

- (void) resume;

- (id) call;

+ (void) yieldToCaller: (id)value;

/** Returns YES if this is the currently executing coroutine. */

@property (readonly) BOOL isCurrent;

/** The number of bytes of stack space left on this coroutine. */

@property (readonly) size_t bytesLeftOnStack;

/** Returns YES if this coroutine is almost out of stack space (less than 8k left) */

@property (readonly) BOOL stackSpaceAlmostGone;

+ (void) setDefaultStackSize: (size_t)stackSize;

@end