Questions tagged [functional-programming]
Use this tag for programs where "functional" style is important - likely making use of function composition and without side-effects. NOT simply because your code contains functions!
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fmap for containers in c++
I implemented a simple fmap for containers. However containers don't have a unified function to add elements. So I wrote different concepts for different containers. Is there a better way to implement ...
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In Java, replace for loop with condition with lambdas [closed]
I want to replace a for loop with a break/return condition inside with a lambda.
I think I have a good replacement, but I want ...
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1
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Sprinkler effect
Developed around visibility CSS property and HTMLElement#offsetHeight and ...
user283117
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3
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Get the contents of a table cell for all selected rows
I have a table of user info. When you click the button, I want to get the email address from each selected row, output into a comma-separated string.
I got it to work with the following code, but I'm ...
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Function composition in the context of data processing pipelines
Prior Notification
This follows a previous review of mine that addressed the core helper function named make_skippable.
The composition implementation presented ...
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Extending callable signature with std::optional in context of function composition (make_skippable)
(Please note: the post about the compose implementation announced below is now available.)
This is about decorating callables by making their argument and return value to be a ...
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Map coloring algorithm functional implementation in python
I'm an autodidact working on map coloring algorithms with backtracking, see chapter 2 of this book.
I tested this implementation with success but I'm still unsure whether it is tricking me somewhere, ...
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Locate and multiply numbers in a 2D grid (Advent of Code 2023 Day 3, Part 2)
I am using the Advent of Code 2023 to study functional programming and the ranges library in C++. This code is for the second part of Day 3 and is the best solution using FB I've created. I'd ...
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Is it valid to pass struct through std::fold_left to persist state?
I am exploring functional programming design with C++. The code below uses a struct passed to ranges::fold_left for processing. The final result is returned in the ...
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Move timestamp to the next Monday 10:01 AM [closed]
I've been battling ChatGPT for hours now and can't get satisfied with this simple algorithm in TypeScript. These two (hopefully correct) TypeScript+ReactNative solutions should move the timestamp ...
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Print the three most occurring chars in Java using streams
The three characters that occurs most in a given string should be printed by using streams/lambdas (functional programming). The order of characters that occur equally often should be preserved.
My ...
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Sequentially find the indexes of an element into a collection
Util class to find into a collection the indexes of a given element with multiple occurrences from the first index or relative to a given index.
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user277679
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Merging sorted integer arrays (without duplicates)
I have written a Python function called merge_arrays which takes two lists and returns the new list merge without duplicate.
The function works as expected, but my ...
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Simple Curry function
This is a interview practice question from BFE.dev.
Currying is a useful technique used in JavaScript applications.
Please implement a curry() function, which ...
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0
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Functional style dependency injection to make business logic unit-testable
My project is a blogging app, which is a recruitment assignment. It is now finished and working.
Following function handles updating a comment votes, very similar as on StackExchange sites, preventing ...
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Imrove performance when updating DataFrame rows based on complex criteria
My question got rejected the last time so I am trying a better approach to getting a solution:
...
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Partial Function Application in JavaScript
I'm trying to make a partial function from any function.
Here is a working example:
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Click temporization on user interface elements
Implementation to accommodate different behaviours based on the frequency a user interface element is clicked. It supports number of clicks and number of clicks in a time frame.
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Dyalog APL dyadic operator deriving ambivalent function to pair two function results
I'm writing a small utility operator which applies two functions to an argument pair and strands the results. The pair can either be given as two arguments or as a single argument with two elements. ...
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LeetCode 399 Evaluate Division using Scala
In order to gain familiarity with Scala I am trying to solve the following problem
https://leetcode.com/problems/evaluate-division/description/
You are given an array of variable pairs equations and ...
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Removing Elements from an Array Based on a Second Array
I've written a function that takes two arrays of integers as input and removes all the elements in the first array that are also present in the second array. I would like to share my code with you and ...
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Optimizing the Dig Pow function
I have written a Python function to solve the Dig Pow problem, where the goal is to find a number k such that the sum of each digit of n raised to a specific and ...
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Optimizing a function to find the closest multiple of 10
I have written a Python function called closest_multiple_10() which takes an integer as input and returns the closest multiple of 10. The function works as expected,...
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Binary tree zipper with basic operations
I am looking for a review of my Binary Tree Zipper implementation on Ocaml.
These are the defined operations:
get (gets the substructure, or the trees after the focus element)
bempty creates an empty ...
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Creating functions in a hierarchy where they get the same arguments
When I write code, I tend to follow functional paradigms often. The main thing I try to do is use values returned from functions.
What I notice though, is I end up having a sort of function argument ...
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Lazy evaluation vs strict one applied to fib
I have this OCaml problem:
Recall the polymorphic type lazy seen in class, the function delay which transforms a ...
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Monad object in C++
Have I defined a Monad object for C++? Below is a class called var which I created years ago to implement a lambda calculus like interpreter in C++. The class ...
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Breaking a string expression in operator and operands
Requesting for a code review for a scala implementation.
Problem
Given an expression string made of numbers and operators +,-,/,* , break it in a list of Integer or ...
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Abundant number implementation
I have implementted a simple JavaScript function to find the list of abundant numbers and print them on the screen.
an abundant number is a number for which the sum of its proper divisors is greater ...
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1
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Transform an array into object and set index for an unique key in javascript
I have a method that merges keys and indexes from an array into an object.
I'm stuck with ways to compress this method, and I don't know what I can do to make it simpler.
Goal
get an array of objects ...
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A Haskell-style "maybe" type in Python, version 2
I have decided on a preferred solution to my question A maybe type in Python. Which implementation is best?, and have expanded it to be more ergonomic. I have implemented a host of utility functions (...
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Reactjs Component Reusability
I am working on a project in react. Where most of the data on different tabs have a table. So I design the "TableItems" component and passed the data according to the component. Right now ...
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Create a function with two parameters: a list and a string, where the string has the following values [closed]
I tried so many things to do this task. I have no idea why doesn't it work. Please help!
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Meta Collatz Sequence
Context
Chapter 6 of Learn You A Haskell contains a function called chain, which outputs the Collatz sequence of a given input.
(In short, it takes a natural number....
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Simplify a function which performs manipulation of data in Javascript
Upon suggestion in the original question within Stack Overflow, I'm bringing my question here.
We have created a function that will convert the data into the desired format, but it has a lot of code ...
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2
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Project Euler 11 Haskell - Largest product in a grid
Intro
I have been learning haskell and functional programming using random Project Euler problems. Currently, I have solved Problem 11.
What is the greatest product of four adjacent numbers in the ...
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MP3 Playlist Class in Python
Background Info
I am an intermediate level Python programmer. This is my implementation of a MP3 Playlist class challenge that was hosted on 101 Computing.Net. The ...
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Commented Parser Combinators in Lisp-style C
I've attempted to remedy the issues outlined in the answer to my previous question. I've added several hundred blank lines to better illustrate the grouping of functions and generally make things look ...
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Parser Combinators in C redux
A few more rewrites down the line from my previous question, this is the C version 11 based on the PostScript prototype version 12. The PostScript version is shorter, but it's some crazy ass ...
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Reusable and testable JavaScript code for URL fragment-based tab navigation logic
Foreword
As a personal project, I've been creating a SPA blog (available here), which features 4 tabs (Thoughts, Projects, Readings, and CV), each accessible via one of four radio buttons, and several ...
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UPDATE on Newspaper Bill Calculator CLI with Python (1 of 3, Core)
Code is posted after explanation.
Due to the size of the project, this is being posted in three separate posts. This also ensures each post is more focused.
Post 2 of 3, CLI: UPDATE 1 on Newspaper ...
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Testing whether one interval overlaps other intervals
I recently started to learn functional programming and wan't to know If I'm doing things right.
I use @effect-ts/core lib as well as ...
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Functional Fibonacci in OCaml
I'm very new to OCaml, and as an exercise I decided to implement the nth Fibonacci algorithm (return a specific Fibonacci number, given an index) in different ways, using what I've learned so far.
I ...
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Newspaper Bill Calculator CLI with Python (1 of 3, Core)
Code is posted after explanation.
Due to the size of the project, this is being posted in three separate posts. This also ensures each post is more focused.
Post 2 of 3, CLI: Newspaper Bill ...
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vote
1
answer
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Convert from get response to array of type
I would like to know if this is the best/most efficient/industry standard way of converting from the http response to an array of typed values:
Type class:
...
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Fizzbuzz Solution - complexity, readability, performance, lines, obfuscation... - .sort()
The fizzbuzz challenge presents a lot of interesting questions for 'intermediate' programmers like myself. I have found that I don't actually know where to draw the line with, complex (hard to read ...
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Haskell: implementing Read for a custom dynamic value type
I'm using Haskell to interpret a dynamically-typed language. I have a sum type called Value which can represent some basic objects:
...
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Suggestions for improvement for generic array and map functions in Go 1.18
Yesterday I build some generic functions for the new official Golang 1.18 release. What do you think about it and what could be added and improved?
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