y.h

//
//  y.h
//
//  A Y-combinator for Objive-C
//
// Copyright (C) 2011 by Joshua Ballanco
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
//

#import <Foundation/Foundation.h>


typedef id (^RecurBlock)(id);
#define YComb(function_block) (RecurBlock) ^(RecurBlock f) {\
                                return (RecurBlock) ^(RecurBlock x) {\
                                  return Block_copy(^(id args) {\
                                    ((RecurBlock)f((id)x((id)x)))(args);\
                                  });\
                                }((RecurBlock) ^(RecurBlock x) {\
                                  return Block_copy(^(id args) {\
                                    ((RecurBlock)f((id)x((id)x)))(args);\
                                  });\
                                });\
                              }((RecurBlock) ^(RecurBlock this_block) {\
                                return Block_copy(function_block);\
                              });\