苹果的apinotes文件

Github-apinotes

http://apinotes.com

API Notes README

API notes provide a mechanism by which Objective-C APIs can be annotated with additional semantic information not present within the original Objective-C headers. This semantic information can then be used by the Swift compiler when importing the corresponding Objective-C module to provide a better mapping of Objective-C APIs into Swift.

API notes are organized into a set of .apinotes files. Each .apinotes file contains annotations for a single Objective-C module, written in YAML (FIXME: to be) described below. These YAML sources must be manually compiled into a binary representation (.apinotesc) that the Swift compiler will lazily load when it builds code, also described below.