(into (vector-of :int) [Math/PI 2 1.4]);=[3 2 1](into (vector-of :char) [100 102 104]);=[\d \f \h](into (vector-of :boolean) [false true 1 nil]);=[false true true false](into (vector-of :long) ["string" "number" 10000]);=ClassCastException java.lang.String cann...
在Clojure中,可以使用Boolean/parseBoolean方法将字符串转换为布尔值。以下是一个示例: 代码语言:clojure 复制 (defn string-to-boolean [str] (Boolean/parseBoolean str)) (string-to-boolean "true") ; 返回 true (string-to-boolean "false") ; 返回 false 这个函数接受一个字符串作为参数,并将其转换为...
1. user=> (f1 1 2) ClassCastException java.lang.String cannot be cast to java.lang.Number clojure.lang.Numbers.add (Numbers.java:128) 1. 对比上面的两端代码,即使函数f1中含有类型有误的表达式(+ "1" 2)也是可以定义的。然而一旦运行的时候(我们随意给了两个没有用到的参数),函数+会尝试将"1"...
(with-open[rdr((comp io/reader io/resource)input-file)](apply+(let[lines(skip(line-seq rdr))](->>lines(remove(set(for[line lines:while(.startsWith line"#")]line)))(map read-string))) 或者 代码语言:javascript 复制 (with-open[rdr((comp io/reader io/resource)input-file)](apply+(...
(defncompare[a b](cond(number?a)(compare-numbersa b)(string?a)(compare-stringsa b)))(defncompare-numbers[a b](.compareToa b))(defncompare-strings[a b](.compareToa b)) 匿名函数 Clojure 支持匿名函数。例如,以下代码定义了一个将列表中的所有元素相加的匿名函数: ...
ClassCastException java.lang.String cannot be cast to java.lang.Number clojure.lang.Numbers.add (Numbers.java:128) 对比上面的两端代码,即使函数f1中含有类型有误的表达式(+ "1" 2)也是可以定义的。然而一旦运行的时候(我们随意给了两个没有用到的参数),函数+会尝试将"1"和2投射(cast)到Java中的Number...
此时数组的元素类型还不是数字(Number),我们使用(map read-string )将元素转换为对应的数字类型,如:["1.3" "2.7"] -> [1.3 2.7]。之后,分别提取数组的第一、二个元素以及两者的和。最后,写入到wtr中。 注意:程序中的str/split是通过(:require [clojure.string :as str])方式引入str命名空间的。
(every? #(instance? String %) stooges) ; -> true (not-every? #(instance? String %) stooges) ; -> false (some #(instance? Number %) stooges) ; -> nil (not-any? #(instance? Number %) stooges) ; -> true
Clojure namespacesareGuile modules (which have very comparable semantics), and the entire Clojure namespace tree is situated under(lokke ns)in the Guile module tree, i.e.clojure.stringis implemented by the(lokke ns clojure string)module, andclojure.string/joinis exactly equivalent to a Guile ref...
There are some areas in which there is no clear consensus in the Clojure community regarding a particular style (like semantic indentation vs fixed indentation, semantic comments vs uniform comments, etc). In such scenarios all popular styles are acknowledged and it’s up to you to pick one an...