用常量映射序列
如果我需要为映射到序列项的函数提供一个常量值，有没有比我目前正在做的更好的方法：
(map my-function my-sequence (cycle [my-constant-value]))
其中 my-constant-value 是一个常量，因为它是my-sequence 上的映射将是相同的，尽管它本身可能是某些更远的函数的结果。我感觉稍后我会看看我在这里问的问题，并认为这是一个愚蠢的问题，因为如果我以不同的方式构建我的代码，那不会是一个问题，但事实就是如此！
If I need to provide a constant value to a function which I am mapping to the items of a sequence, is there a better way than what I'm doing at present:
(map my-function my-sequence (cycle [my-constant-value]))
where my-constant-value is a constant in the sense that it's going to be the same for the mappings over my-sequence, although it may be itself a result of some function further out. I get the feeling that later I'll look at what I'm asking here and think it's a silly question because if I structured my code differently it wouldn't be a problem, but well there it is!
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评论（4）
在您的情况下，我将使用匿名函数：
使用部分应用的函数是另一种选择，但在这种特定情况下没有多大意义：
您（也许？）需要重新定义 my-function 以将常量值设为第一个参数，并且您不需要接受可变数量的参数，因此使用
partial不会给您带来任何好处。In your case I would use an anonymous function:
Using a partially applied function is another option, but it doesn't make much sense in this particular scenario:
You would (maybe?) need to redefine my-function to take the constant value as the first argument, and you don't have any need to accept a variable number of arguments so using
partialdoesn't buy you anything.我倾向于使用部分或匿名函数，如 dbyrne 建议的那样，但另一个需要注意的工具是
repeat，它返回一个无限序列，无论你想要什么值：I'd tend to use partial or an anonymous function as dbyrne suggests, but another tool to be aware of is
repeat, which returns an infinite sequence of whatever value you want:我发现有时比
map更具可读性的另一种方法是for列表理解宏：Yet another way that I find sometimes more readable than
mapis theforlist comprehension macro:是的:)来自 API 的“其他有用的函数” 部分的小宝石
不断(map my-function my-sequence (constantly my-constant-value))(map compines-data Something-new a-constant) 的模式在 idomatic clojure 中相当常见。对于分块序列等，它也相对较快。
编辑：这个答案是错误的，但是
constantly和其余的“其他有用的函数”api 非常酷，无论如何我想将这里的引用留给他们。yep :) a little gem from the "other useful functions" section of the api
constantly(map my-function my-sequence (constantly my-constant-value))the pattern of (map compines-data something-new a-constant) is rather common in idomatic clojure. its relativly fast also with chunked sequences and such.
EDIT: this answer is wrong, but
constantlyand the rest of the "other useful functions" api are so cool i would like to leave the reference here to them anyway.