Clojure中的'（）和（list）之间有什么区别？ [英] What's the difference between '() and (list) in Clojure?

问题描述

列表上的 API Cheatsheet 部分似乎表明'（）是一个列表构造函数，就像（list），但我发现在实践中他们不完全一样。例如，给定：

The API Cheatsheet section on Lists seems to indicate that '() is a list constructor, just like (list), but I've found that in practice they're not exactly the same. For example, given:

(def foo "a")
(def bar "b")
(def zip "c")

以下语句：

(apply str '(foo bar zip))

$ b

produces the output "foobarzip", which I wouldn't expect.

但是假设的是等价的：

(apply str (list foo bar zip))

产生abc，如我所料。

produces "abc", as I'd expect.

这是怎么回事？如果在Clojure中有一个列表的简写（例如 {} 表示映射， [] 表示向量）是什么？

What's going on here? If there's a "shorthand" for a list in Clojure (like {} for maps and [] for vectors), what is it?

推荐答案

在lisps中，'

换句话说'（foo bar zip）创建一个包含符号 foo ， bar ， zip ; （list foo bar zip）创建一个包含 foo ， bar ， zip 。在第一种情况下， str 会将符号本身转换为字符串，然后将它们连接起来。

To put it another way '(foo bar zip) creates a list containing the symbols foo, bar, zip; while (list foo bar zip) creates a list containing the values of foo, bar, zip. In the first case, str will be converting the symbols themselves to strings and then concatenating them.

：

=> (def foo "a")
=> (type (first '(foo)))
clojure.lang.Symbol
=> (type (first (list foo))) 
java.lang.String

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