const strats = Object.create(null)
function defaultStrat(val1: any, val2: any): any {
return typeof val2 !== ‘undefined’ ? val2 : val1
}
function fromVal2Strat(val1: any, val2: any): any {
if (typeof val2 !== ‘undefined’) {
return val2
}
}
const startKeysFromVal2 = [‘url’, ‘params’, ‘data’]
startKeysFromVal2.forEach(key => {
strats[key] = fromVal2Strat
})
老师,strats[key] = fromVal2Strat中这个fromVal2Strat明显是一个函数,为啥不是fromVal2Strat()调用,而且他怎么保证start[key]和fromVal2Strat中的val2一一对应呢