functional-programming

问题 I have a list, e.g like: val list = listOf("orange", "apple", "apple", "banana", "water", "bread", "banana") How can i check how many times apple is duplicated in this list? 回答1: list.count { it == "apple" } Documentation: https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.collections/-list/, https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.collections/count.html 回答2: One way to find all the repeated values in a list is using groupingBy and then filter the values which are > 1 . E.g. val

问题 I have a list, e.g like: val list = listOf("orange", "apple", "apple", "banana", "water", "bread", "banana") How can i check how many times apple is duplicated in this list? 回答1: list.count { it == "apple" } Documentation: https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.collections/-list/, https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.collections/count.html 回答2: One way to find all the repeated values in a list is using groupingBy and then filter the values which are > 1 . E.g. val

问题 How is a JUMP and CALL instruction different? How does it relate to the higher level concepts such as a GOTO or a procedure call? (Am I correct in the comparison?) This is what I think: JUMP or GOTO is a transfer of the control to another location and the control does not automatically return to the point from where it is called. On the other hand, a CALL or procedure/function call returns to the point from where it is called. Due to this difference in their nature, languages typically make

问题 Do you have any idea how to retrieve all SimpleProperty from TopComplexity object? I need to change that for loop into stream "kind" piece of code. @Data public class TopComplexity { List<SuperComplexProperty> superComplexProperties; } @Data public class SuperComplexProperty { List<SimpleProperty> simpleProperties; ComplexProperty complexProperty; } @Data public class ComplexProperty { List<SimpleProperty> simpleProperties; } public class MainClass { public static void main(String[] args) {

问题 When I input Seq(1,2,3) in REPL, it returns me List(1,2,3) scala> Seq(1,2,3) res8: Seq[Int] = List(1, 2, 3) Therefore, I thought the List(1,2,3) may be of type List[Int] . And I tried to specify the type for the variable who are assigned to Seq(1,2,3) , but unexpectedly, the REPL complains like this: scala> val a:List[Int]=Seq(1,2,3) <console>:20: error: type mismatch; found : Seq[Int] required: List[Int] val a:List[Int]=Seq(1,2,3) Does anyone have ideas about what Seq[Int] = List(1, 2, 3)

问题 When I input Seq(1,2,3) in REPL, it returns me List(1,2,3) scala> Seq(1,2,3) res8: Seq[Int] = List(1, 2, 3) Therefore, I thought the List(1,2,3) may be of type List[Int] . And I tried to specify the type for the variable who are assigned to Seq(1,2,3) , but unexpectedly, the REPL complains like this: scala> val a:List[Int]=Seq(1,2,3) <console>:20: error: type mismatch; found : Seq[Int] required: List[Int] val a:List[Int]=Seq(1,2,3) Does anyone have ideas about what Seq[Int] = List(1, 2, 3)

问题 When I input Seq(1,2,3) in REPL, it returns me List(1,2,3) scala> Seq(1,2,3) res8: Seq[Int] = List(1, 2, 3) Therefore, I thought the List(1,2,3) may be of type List[Int] . And I tried to specify the type for the variable who are assigned to Seq(1,2,3) , but unexpectedly, the REPL complains like this: scala> val a:List[Int]=Seq(1,2,3) <console>:20: error: type mismatch; found : Seq[Int] required: List[Int] val a:List[Int]=Seq(1,2,3) Does anyone have ideas about what Seq[Int] = List(1, 2, 3)

问题 If I have one or more recursive functions inside an Ocaml function how can I call them without exit from the main function taking their value as return of the main function? I'm new in Ocaml so I'll try to explain me better... If I have : let function = let rec recursive1 = ... ... let rec recursive2 = ... ... How can I call them inside function to tell it "Hey, do you see this recursive function? Now call it and takes its value." Because my problem is that Ocaml as return of my functions

问题 If I have one or more recursive functions inside an Ocaml function how can I call them without exit from the main function taking their value as return of the main function? I'm new in Ocaml so I'll try to explain me better... If I have : let function = let rec recursive1 = ... ... let rec recursive2 = ... ... How can I call them inside function to tell it "Hey, do you see this recursive function? Now call it and takes its value." Because my problem is that Ocaml as return of my functions

问题 If I have one or more recursive functions inside an Ocaml function how can I call them without exit from the main function taking their value as return of the main function? I'm new in Ocaml so I'll try to explain me better... If I have : let function = let rec recursive1 = ... ... let rec recursive2 = ... ... How can I call them inside function to tell it "Hey, do you see this recursive function? Now call it and takes its value." Because my problem is that Ocaml as return of my functions