Erlang 中非短路布尔运算符有什么用？
我正在通过 LearnYouSomeErlang 网络书学习 Erlang。在学习时令我印象深刻的一件事是非短路布尔合取和析取运算符，即； 和和或。这些运算符的用例是什么？为什么要使用它们而不是 andalso 和 orelse？
I am learning Erlang from the LearnYouSomeErlang web-book. One thing that struck me while learning was the non short-circuiting boolean conjunction and disjunction operators viz; and and or. What are the use cases for these operators? Why would you want to use them instead of andalso and orelse?
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过去（直到 R13A）
andalso和orelse不是尾递归。有关详细信息，请参阅 http://www.erlang.org/eeps/eep-0017.html。我认为没有充分的理由在新程序中使用and/or。It used to be (until R13A) that
andalsoandorelseweren't tail recursive. See http://www.erlang.org/eeps/eep-0017.html for details. I don't think there is a good reason to useand/orin new programs.我认为它们在做不同的事情，并这样使用它们：
and/or作为逻辑运算符，我想在其中比较逻辑值。由于它们很严格，我会自动进行类型检查，并且我知道确切地调用了什么。andalso/orelse用于控制，很像 C 中的&&和||。查看错误的定义在 erlang 中，我觉得很高兴知道已经执行了什么以及它是如何执行的。
I see them as doing different things and use them as such:
and/oras logical operators where I want to compare the logical values. As they are strict I automatically get type-checking and I KNOW exactly what has been called.andalso/orelsefor control, much like&&and||in C.Seeing errors are defined in erlang I feel it is good to know what has been executed and how it went.
和/或运算符的历史要悠久得多。 andalso/orelse 运算符是后来添加的。和/或今天的用例可能是当您只想执行一些简单的布尔运算时，并且水平空间比可能节省几个机器周期更重要。例如：
而不是
对眼睛更容易一些。
出于向后兼容性的原因，不可能仅更改原始行为和/或变得短路，因此需要新的关键字。名称 andalso/orelse 来自标准 ML。
The and/or operators are simply much older. The andalso/orelse operators are later additions. A use case for and/or today could be when you just want to perform some simple boolean operations and horizontal space is more important than possibly saving a couple of machine cycles. For example:
rather than
is a bit easier on the eyes.
For reasons of backwards compatibility, it wasn't possible to just change the behaviour of the original and/or to become short-circuiting, so new keywords were needed. The names andalso/orelse come from Standard ML.