First-class functions can be assigned to variables, passed to other functions as arguments, or returned from other functions. The ability to return a function enables deferred execution. Functions that accept other functions as arguments are called higher-order functions.
Questions tagged [first-class-functions]
132 questions
0
votes
1 answer
In Python, how do I change which class's attribute a function will look for based on a parameter?
I'd like to use the same function twice but change which class attribute the function will use. It would look similiar to below:
class Player:
def __init__(self):
self.primary_color = 'blue'
self.secondary_color = 'pink'
def…
NateBradshaw
- 9
- 1
0
votes
1 answer
type mismatch when create a kotlin infix notation to nest a function to another
I am trying to create a infix notation as a extension function of (Int) -> Int function which is used to nest a function to another.
For example:
class Entry {
companion object {
private fun f(x: Int) = x * 2
private fun g(x:…
Langua
- 3
- 2
0
votes
2 answers
what is the different between Function first class and void function in Dart
in order to optimize my code, I try to use Function first class in the onTap property of the GestureDetector widget, like in the code below:
import 'package:flutter/material.dart';
class ReusableCard extends StatelessWidget {
final Color…
Taha Kerrouzi
- 177
- 2
- 15
0
votes
1 answer
How to call a function stored as variable with arguments - Python 3
def some_function():
print("This will always be the same")
def some_other_function(text):
print(text)
some_variable = "hello"
list_of_elements = [
"element_one": {
"name": "static_print",
"function": some_function
…
CyberGeneticist
- 83
- 11
0
votes
3 answers
Difficulty Iterating Through Function Call - First Class Functions
The code I have provided executes properly, however as you will see it offers refreshments to each guest repeatedly before moving on to the next guest.
I'm scratching my head as to how I can alter my code, in an efficient way, so that each customer…
Lil' Big Boy
- 21
- 6
0
votes
1 answer
python: assigning first class function to dictionary item
I have an existing dictionary and I want to add new element as a first-class function generated from a list.
Is there a more pythonic way of doing this?
agg_dict = {}
for x in attribute_list:
agg_dict[x] = lambda x: ','.join(x)
I've tried using…
little_stone_05
- 145
- 1
- 9
0
votes
2 answers
Is there any difference between First Class Functions and Callback Functions in Javascript?
Are there any differences between first class functions and callback functions in javascript? I thought that first class functions were functions that were treated as regular variables and can be passed as arguments. Aren't callback functions the…
I_keep_getting_downvoted
- 100
- 11
0
votes
1 answer
Does fortran have first-class function?
In Fortran, we can pass a function name as an argument to a subroutine/function.
Does this mean that fortran has first-class functions?
The answer seems to be no, since it seems that fortran does not support returning functions as the values from…
Youjun Hu
- 991
- 6
- 18
0
votes
0 answers
Why is a list of anonymous closures not identical to a list of evaluations of anonymous enclosing functions?
Note: This concept is touched upon in Lambda function in list comprehensions, but not to a sufficient depth for my understanding.
We start with an example (in Python) of a closure:
def enclosing_function(free_variable):
def nested_function(x):
…
Jon Middleton
- 363
- 1
- 3
- 8
0
votes
1 answer
What alternative when I get: "Partial application of 'mutating' method is not allowed"
When I do this:
struct Test {
var value: Int = 0
mutating func increment(amount: Int) { value += amount }
mutating func decrement(amount: Int) { value -= amount }
func apply(technique: (Int) -> ()) {
print("Before:\(value)")
…
Cortado-J
- 2,035
- 2
- 20
- 32
0
votes
3 answers
Executing higher-order functions
I'm learning the concepts of first class functions and closures in Python and I was curious to know:
Given a higher-order function:
def html_tag(tag):
def wrap_text(text):
print("<{0}>{1}".format(tag, text))
return…
Dave Kalu
- 1,520
- 3
- 19
- 38
0
votes
4 answers
How to implement currying in javascript?
Question as below:
create a sum function, and the requirement:
sum(1,2).result === 3
sum(1,2)(3).result == 6
sum(1,2)(3,4).result == 10
sum(1,2)(3,4)(5).result == 15
This is a question about currying in JS. I have implemented the most functions…
Wayne Ho
- 45
- 1
- 8
0
votes
3 answers
trying to do math, int object is not callable
def square(x):
int(x)
return 2(x * x)
def my_map(func, arg_list):
result = []
for i in arg_list:
result.append(func(i))
return result
squares = my_map(square, [1,2,3,4,5])
print(squares)
i'm trying to pass a number to…
anthony pizarro
- 135
- 7
0
votes
1 answer
Type mismatch on basic "apply twice" hello world in Haskell
The minimal code:
twice :: (a -> a) -> a -> a
twice f = f . f
main = do
return twice ++ "H"
The errors generated:
stack runhaskell "c:\Users\FruitfulApproach\Desktop\Haskell\test.hs"
C:\Users\FruitfulApproach\Desktop\Haskell\test.hs:5:1:…
MathCrackExchange
- 595
- 1
- 6
- 25
0
votes
4 answers
JS :: First Class Functions :: Parameter Value Confusion
I do not understand how the parameter of the first class function, "number", has the value it does.
I have been mulling over this problem for a couple of days and I am not making any progress in my thinking. There is no error code as this is…
sector7g
- 5
- 3