Either从未真正成为基于异常处理的结构.它旨在表示一种情况，其中一个函数实际上可能返回两种不同类型中的一种，但是人们开始约定，左类型应该是失败的情况，而右类型是成功的情况.如果要为某些通过/失败类型业务检查逻辑返回偏倚类型，则scalaz中的Validation效果很好.如果您有一个可以返回值或Throwable的函数，那么Try将是一个不错的选择. Either应该用于您确实可能会获得两种可能的类型之一的情况，并且现在我正在使用Try和Validation(每种用于不同类型的情况)，我再也不会使用Either了.

Either was never really meant to be an exception handling based structure. It was meant to represent a situation where a function really could possible return one of two distinct types, but people started the convention where the left type is a supposed to be a failed case and the right is success. If you want to return a biased type for some pass/fail type business checks logic, then Validation from scalaz works well. If you have a function that could return a value or a Throwable, then Try would be a good choice. Either should be used for situations where you really might get one of two possible types, and now that I am using Try and Validation (each for different types of situations), I never use Either any more.