Questions tagged [higher-order-functions]
Higher-order functions are functions which either take functions as arguments or return them as output (or both). They are a cornerstone of functional programming.
higher-order-functions
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Type for heterogeneous *args
In typed Python, how do you type a *args list that you're expecting to pass to another argument that is a higher kinded function?
For example, this function takes a function and its first argument and ...
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How does <$ = (fmap . const) in Functor even work in Haskell?
I know that the dot (.) operator takes two functions which both take an argument respectively, and the third argument for the second argument.
Its type is (.) :: (b -> c) -> (a -> b) -> a -...
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Create a list accumulating the results of calling a function repeatedly on an input value
Is there a library function that creates recursive lists in the following sense,
recursive_list(f, x0, n) = [x0, f(x0), f(f(x0)), f(f(f(x0))), ...]
with n elements in the returned list?
If not, how ...
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Appropriate defining equations for Haskell functions
The task is to give appropriate defining equations for the following functions:
curry :: ((a, b) → c) → a → b → c
uncurry :: (a → b → c) → (a, b) → c
curry takes one function and two types (a,b) ...
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I don't understand this example for a callback function, in which we callback a function which hasn't actually been declared
In the below example from Codecademy, I don't really understand how the console can process the 'artist' parameter in a higher-order function, considering that we've only declared 'artists' up to this ...
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How does this nested lambda function work?
How do we get the output of 120?
I don't quite understand what is x(y) in the function. Which arguments are passed into which function?
def combinator(y):
return (lambda x: lambda y: x(y))(lambda x:...
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why is my higher order function returning true and false?
I have to create my own higher order filter() function to filter an array of 10 words that only returns word that have 6 or more letters but my function is only returning true and false and not ...
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Understanding use of closure in callback in javascript [duplicate]
I am trying to understand how closure is used in callback function in javascript.Can anybody explain me in detail ?
function fetchData(url, callback) {
fetch(url)
.then((response) => ...
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How do I pass a generic function as an argument to another function in golang?
How do i modify transformNumbers function so that it works with generic function doubleG and tripleG
type trandformFn func(int) int
func transformNumbers(numbers *[]int, transform trandformFn) []int {...
- 384
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How does combining higher-order functions work in JavaScript?
The first book I have bought on JavaScript was unfortunately not for beginners.
The book is "the joy of JavaScript" from Luis Atencio. I am still trying to understand some concept in this ...
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SiCP Exercise 1.45
Update: I changed the argument 1 in nth-root to 1.0, and then it works.
Why are they different?
Here's my original question.
I have
(define tolerance 0.00001)
(define (fixed-point f first-guess)
(...
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Custom JVP and VJP for higher order functions in JAX
I find custom automatic differentiation capabilities (JVP, VJP) very useful in JAX, but am having a hard time applying it to higher order functions. A minimal example of this sort is as follows: given ...
- 303
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How can I get strongly-typed higher order functions in Typescript?
See the below code block:
interface TestHiveInput {
input: string;
}
interface TestHiveOutput {
output: string;
}
type ListenFunction = (value: any) => void;
type Hive<T, K> = (...
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Linear combination of functions in C++
Let's say we have the following:
// some functions
double f1( double x );
double f2( double x );
double f3( double x );
// coefficients
double c1, c2, c3;
// input variable
double x;
We need to ...
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Need help understanding whether internal state of viewModel is automatically updated along with ProtoDataStore
Working on an android app (personal project) with Kotlin and Jetpack.
Using Proto datastore to store application settings/configurations. Using Hilt for D.I.
My code was just working fine with ...
