以下代码是WWDC中的中级 Swift谈话示例的派生.我要做的是从一个键属性列表初始化一个模型类,它来自某种API. class Movie { var title: String init(title: String) { self.title = title }}func movieFromDictiona
class Movie { var title: String init(title: String) { self.title = title } } func movieFromDictionary(dict: Dictionary<String, AnyObject>) -> Movie? { switch dict["title"] { case .Some(let movieTitle as String): return Movie(title: movieTitle) default: return nil } }
当我尝试编译这些时,我收到以下错误:
Bitcast requires both operands to be pointer or neither %38 = bitcast i8* %37 to %SS, !dbg !161 Invalid operand types for ICmp instruction %39 = icmp ne %SS %38, null, !dbg !161 PHI nodes must have at least one entry. If the block is dead, the PHI should be removed! %42 = phi i64 , !dbg !161 PHI node operands are not the same type as the result! %41 = phi i8* [ %38, %34 ], !dbg !161 LLVM ERROR: Broken function found, compilation aborted! Command /Applications/Xcode6-Beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swift failed with exit code 1
有趣的是编辑器似乎对代码没问题.这是编译器错误还是代码有问题?
我同意评论者这是一个编译器错误,你应该向苹果报告.但是,您也可以通过这种方式实现它,这更简单,应该可以正常工作:func movieFromDictionary(dict: Dictionary<String, AnyObject>) -> Movie? { if let title = dict["title"] as? String { return Movie(title: title) } else { return nil } }