流程和功能定义

Question

我正在尝试在flow中定义功能签名。我希望以下代码抛出错误，但我没有收到任何错误？

// function that applied a function to an array - just for numbers
const arrayMath = (func: () => number, arr: Array<number>):Array<Number> => arr.map(func);

// would expect this function to work OK with arrayMath
const square = (num: number): number => num * num;

// would expect this function to fail with arrayMath
const concatX = (str: string): string => `${str}X`;

// flow is not giving me an error here..
arrayMath(concatX, [1, 2, 3]);

Answer 1

看来流程确实发现了您发布的代码的错误。

https://flow.org/try/#0PTAEAEDMBsHsHcBQiSkgVwHYGMAuBLWTUXACwENdRyAHG6fAUwBNq0s9DjdZrjyATgPIBPUAFpQAK3QBnKpFgDQmdAFsARowGzE2IvOpDRAWUqlQAXlAAKDDgBctgJRWAfCvVaBAGiMCnAEFjEQAeVU1tN2cHYOEwgDkvKPd-ADo1WjsOZwBuZFR4WHRoVkYADxpGPBJSfFl2HAIiEl4igQBrUAB5AGlQeHwyf1NzPQMqWQBHdEFGK1sIpwjvGM9I5UsPCNAAKnX8lDAikrLK6qoyesbOFp40cnxoAaGLQXizMnHMQ30cSgAGgsbPIAqBQfhMABzNYQ6GpAAGABIAN6ggC+AIRh1QMAQoGumFgVCh+AAbpCoaA1PNyMRtAIlKBSNpGGk0oh3qMyDY-thAX4ANoARj8ACY-ABmAC6eSAA