functional-programming

问题 When should I write my functions in curried form? does not match my thought, need to correct myself. As part of my learning link, this is what I understand from function currying. Below is one example: def curry2(f): """Returns a function g such that g(x)(y) == f(x, y) >>> from operator import add >>> add_three = curry2(add)(3) >>> add_three(4) """ def g(x): def h(y): return f(x, y) return h return g In any application, if I know that the number of arguments are fixed (say 2 arguments) and

问题 When should I write my functions in curried form? does not match my thought, need to correct myself. As part of my learning link, this is what I understand from function currying. Below is one example: def curry2(f): """Returns a function g such that g(x)(y) == f(x, y) >>> from operator import add >>> add_three = curry2(add)(3) >>> add_three(4) """ def g(x): def h(y): return f(x, y) return h return g In any application, if I know that the number of arguments are fixed (say 2 arguments) and

问题 Just for the sake of quick clarity for someone who wants to start working with Scala FP library, on a journey to become better at pure FP. Would someone clarify the difference/relation between Cats and Cats-Effect, Cats-Effects IO? On top of that, where does Zio, and Monix stand with respect to it? Finally, what would be the relation to ScalaZ 7/8? So far based on what I have read, a good combination of the library to work with based on the documentation available and what they do would be

问题 I have created my own type in F# called Accounts and I have then created objects for each account. type Account() = let AccountNumber = "" let mutable Balance:float = 0.0 Every account has two fields, AccountNumber (string) and Balance (float). I have then created an object for every account that holds the AccountName and the Balance. let acc1 = new Account() acc1.Insert("John",10.0) let acc2 = new Account() acc2.Insert("Mike",50.0) How do I create a list that holds each account (object)? I

问题 I have a problem using functors in OCaml. I have a module type TASK that is used to have different kinds of tasks: module type TASK = sig type task_information type task_information_as_lists type abstract_u_set_type module AbstractUSet : Set.S with type t = abstract_u_set_type val mk_task_information : task_information_as_lists -> task_information end A module of type TASK will contain algorithms that use nodes. These nodes will have different types. I therefore built TASK_NODE : module type

问题 I know I can initialize a Map, and then fill it using a stream. For example, here I use an IntStream of random numbers to populate the key of the predefined map. int initialCapacity = 3; Map < Integer, UUID > map = new HashMap <>( initialCapacity ); IntStream numbers = ThreadLocalRandom.current().ints( initialCapacity ); numbers.forEach( number -> map.put( number , UUID.randomUUID() ) ); Dump to console. System.out.println( "map = " + map ); map = {-14054365=ee739423-1200-45e6-80da

问题 I have got two arrays of objects. I want to filter data based on permissionObj. This is coming from database. Here are arrays of sub-arrays in the permissionObj. let permissionObj = [{ "OA deal": [{ label: "can view", value: "can_view" }, { label: "can create", value: "can_create" }, { label: "can edit", value: "can_edit" }, { label: "can delete", value: "can_delete" } ] }, { "Deposit": [{ label: "can view", value: "can_view" }, { label: "can create", value: "can_create" }, { label: "can edit

问题 I have got two arrays of objects. I want to filter data based on permissionObj. This is coming from database. Here are arrays of sub-arrays in the permissionObj. let permissionObj = [{ "OA deal": [{ label: "can view", value: "can_view" }, { label: "can create", value: "can_create" }, { label: "can edit", value: "can_edit" }, { label: "can delete", value: "can_delete" } ] }, { "Deposit": [{ label: "can view", value: "can_view" }, { label: "can create", value: "can_create" }, { label: "can edit

问题 I am trying to create executable file for deploying my web app using play framework sbt dist command. When I run my application using "sbt run" command then https work but when I use sbt dist and run my executable file to start my app then only http url works. Following is my configuration In build.sbt javaOptions ++= Seq( "-Dhttps.keyStore=conf/keystore.jks", "-Dhttps.keyStorePassword=*****", "-Dhttp.port=9000", "-Dhttps.port=9001", "-Dsentry.dsn=https://****" ) In application.conf play.http

问题 I've been banging my head against the wall trying to learn about curried functions. Here's what I understand so far; suppose I have a function: fun curry (a b c) = a * b * c; or fun curry a b c = a * b * c; In ML, I can only have one argument so the first function uses a 3-tuple to get around this / get access to a , b , and c . In the second example, what I really have is: fun ((curry a) b) c where curry a returns a function, and (curry a) b returns a function and ((curry a) b) c returns