anonymous-function

问题 I wrote a function which returns a function based on the String argument it receives. The code looks as follow: def getFunction(str:String) : Map[String, String] => String={ val s = str.charAt(0).toString() s matches { case "x" => (arg:Map[String, String]) => arg("random") case _ =>(arg:Map[String, String]) => arg("") } } This is giving a compilation exception Description Resource Path Location Type missing parameter type for expanded function The argument types of an anonymous function must

问题 I wrote a function which returns a function based on the String argument it receives. The code looks as follow: def getFunction(str:String) : Map[String, String] => String={ val s = str.charAt(0).toString() s matches { case "x" => (arg:Map[String, String]) => arg("random") case _ =>(arg:Map[String, String]) => arg("") } } This is giving a compilation exception Description Resource Path Location Type missing parameter type for expanded function The argument types of an anonymous function must

问题 I have a cell array of anonymous function handles, and would like to create one anonymous function that returns the vector containing the output of each function. What I have: ca = {@(X) f(X), @(X)g(X), ...} What I want: h = @(X) [ca{1}(X), ca{2}(X), ...] 回答1: Yet another way to it: You can use cellfun to apply a function to each cell array element, which gives you a vector with the respective results. The trick is to apply a function that plugs some value into the function handle that is

问题 I have a cell array of anonymous function handles, and would like to create one anonymous function that returns the vector containing the output of each function. What I have: ca = {@(X) f(X), @(X)g(X), ...} What I want: h = @(X) [ca{1}(X), ca{2}(X), ...] 回答1: Yet another way to it: You can use cellfun to apply a function to each cell array element, which gives you a vector with the respective results. The trick is to apply a function that plugs some value into the function handle that is

问题 How could one write the identity function in clojure using anonymous function literal (#())? The following code doesn't work: (#(%) 5) It raises an exception because it is converted to: ((fn[x] (x)) 5) The problem in that when using #() , the function body is enveloped with parentheses. Any idea, how to elegantly overcome this? 回答1: Well, first of all, there is the identity function. But you can use #(do %) if you insist. 来源： https://stackoverflow.com/questions/9148896/in-clojure-how-to-write

问题 How could one write the identity function in clojure using anonymous function literal (#())? The following code doesn't work: (#(%) 5) It raises an exception because it is converted to: ((fn[x] (x)) 5) The problem in that when using #() , the function body is enveloped with parentheses. Any idea, how to elegantly overcome this? 回答1: Well, first of all, there is the identity function. But you can use #(do %) if you insist. 来源： https://stackoverflow.com/questions/9148896/in-clojure-how-to-write

问题 How could one write the identity function in clojure using anonymous function literal (#())? The following code doesn't work: (#(%) 5) It raises an exception because it is converted to: ((fn[x] (x)) 5) The problem in that when using #() , the function body is enveloped with parentheses. Any idea, how to elegantly overcome this? 回答1: Well, first of all, there is the identity function. But you can use #(do %) if you insist. 来源： https://stackoverflow.com/questions/9148896/in-clojure-how-to-write

问题 So I am confused as to when I would use an anonymous function such as: let foo = function () { //code } versus a named anonymous function such as: let foo = function foo () { //code } Besides browser support, namely IE, are there any differences between the two? When should I use one over the other? 回答1: In this case, where the function declaration name is the same as the variable it is assigned to, it doesn't make much difference. If you used a different name for the definition and

问题 I have following setup: In Child component: <template> <div @click="clickHandler"> </div> </template> <script> ... clickHandler() { this.$emit('emittedFunction', someInfo, otherInfo) } </script> In Parent component: <template> <child-component v-for="index in 10" @emittedFunction="(someInfo, otherInfo) => someFunction(index, someInfo, otherInfo)"/> </template> <script> ... someFunction(index, someInfo, otherInfo) { do stuff } </script> This code works perfectly fine. To my question though: A

问题 Inside some functions as dplyr::mutate_at or purrr::map , it seems that one can use tilde operator ~ to build anonymous functions . For example, one can do as in the linked question: map(iris, ~length(unique(.))) Or also: mtcars %>% mutate_all(~.*2) I tried to imitate this inside sapply , to avoid sapply(list, function(item) {something_with_item}) . I was writing sapply(list, ~ something_with_.) but I get an error Error in match.fun(FUN) : '~ something_with_.' is not a function, character or