Questions tagged [f#]
F# is a succinct, expressive, and efficient functional and object-oriented language for .NET
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Divide number by factors
I'm learning F#.
The code below gets a number e.g. 100 and list of factors and should divide that number by the factors without any rest. (There is an actual code I've got in C#, but this is F# port).
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Project Euler #2 in F#
Project Euler Problem 2 asks for the sum of all even Fibonacci numbers below 4 million.
My first attempt at this problem using functional programming with F#. I would've liked to use some kind of ...
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Returning different elements between a Hashtable and list<string> in F#
I have two collections:
A list of strings
A hashtable
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Barnes-Hut implementation of the N-Body problem translated from F# to C#
I am after a peer review of a C# implementation of the Barnes-Hut algorithm which I have translated from F#. The F# version is the base for comparison, therefore the C# version is suppose to reflect ...
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Call an F# function with its previous result until the output no longer changes
Basically I have a function of the type 'a -> 'a (an optimization function on a AST) and I want to call it (passing the previous result) until it returns the ...
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F# thumbnail Scraper
Thumbnail Scraper
I'm a C# programmer learning F#. For my first program I created a console youtube thumbnail scraper. It parses command line arguments with argu and then downloads the thumbnails, ...
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Command line wordle
I am seeking a review of my command line wordle game.
Having only recently started exploring functional programming, I expect that there will be no shortage of areas to improve. This is my first ...
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Sieve of Eratosthenes in F#
after looking at the pseudocode for the Sieve of Eratosthenes on wikipedia I tried implementing a similar version using F#. The code runs just fine, that is, it returns all prime numbers up until a ...
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Download and parse XML data from a URL every minute with F#
The purpose
This code is intended to achieve the following goals:-
Create a hard coded list of lifts, this is pretty static and I add some extra info so I'm ok with this being in the code but I may ...
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F# simple monoalphabetic cipher code implementation
I am a new F# programmer, and a student in a security class. As part of my notes, I wrote a small implementation of a monoalphabetic cipher as follows:
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Cardinal to ordinal numbers in F# code reuse
I've been experimenting with the F# Bolero environment to learn F# a bit and I was trying to get the hang of pattern matching by generating ordinal numbers (1st, 2nd, 3rd, ...) from cardinal numbers (...
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"Rock, Paper, Scissors +" in F#
During a discussion in a development chat, a user suggested to another (in the context of C# originally),
UserA: Challenge: Create an implementation of RPS, and then show how it can be extended to ...
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Retrying failed calls to a crypto exchange
This code represents logic used to retry failed calls to a crypto exchange:
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Simple Password Generator Feedback
This is my first major project in F#, looking for any critique on how I can make it more standard or more concise.
Some things I feel like I could have done better are the command flag parsing and the ...
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Print each word of a sentence in a new line
this is my first F# program, very simple concept but took me a few minutes to get it. I'm new to functional programming so I'd appreciate if you could have a look ...
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How to refactor the boolean logic of this F# function?
I have a list of path I want to filter out. I want to keep only paths matching a specific pattern and remove all paths matching another specific pattern.
To achieve this I pattern matched on each ...
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What would be this best way to show that my function can accept some specific numbers as input? [closed]
I am writing a credit card generator. I have method GenerateVisa() who will return either a 13 or 16 numbers string.
This is the default value but GenerateVisa can ...
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Downloading multiple log files
This code succeeds in downloading log text files from multiple URLs. Can this be made more efficient?
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What would be the idiomatic F# way to write optional parameters?
In the context of a library to generate random credit card, it would be nice to let the user the possibility to set some optional options on some cards. Lets take Visa. Two lengths are available: 13 ...
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Maintaining state while walking a tree structure
The following code creates a simple tree structure and then walks through the tree looking for node with the value 9 that appears after we have seen a node with the value 1 and a node with the value 4 ...
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How to apply multiple filters in one statement
While trying to grasp the potentials of the collection features in F#, I encountered this one:
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Converting a float to a fraction as a string
I was inspired by this video by Matt Parker to use the Farey Sequence to convert a float into a string representation of a fraction, how did I do? How well did I follow F# workflow and patterns (I'm ...
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Handling bill cancellation
I'm trying to refactor the working code below which intends to handle bill cancellation, but doesn't seem "linear" enough.
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How to flatten the nested try-catch block in F#?
How to flatten the nested try-catch block in F# for the following code? I am using EF Core with F#. The nested is required because I need to Rollback the transaction if there are errors in saving or ...
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Refactoring of two command handler implementations with F# in the context of event sourcing
I've written some F# code to handle commands in the context of event sourcing which works along the lines below:
Read Events from a specific event store stream
Build the current state in the given ...
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First-time F#: A simple Rock Paper Scissors
This is my first F# program. It's a simple Rock-Paper-Scissors implementation.
I am looking for feedback of all sorts, e.g. the choice of types (e.g. List vs Array), whether there are parts that could ...
CommunityBot
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CodeWars Deodorant Evaporator
How can I make the solution to this https://www.codewars.com/kata/5506b230a11c0aeab3000c1f/train/fsharp more "functional"?
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F# method to insert, update, or delete events in a dictionary
I have the following code:
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Return early with Error from Sequence mapping
I have put together this f# code in an attempt to solve the following problem
Given a mapping operation that may not be able to return a value
Cease mapping over the remaining items of a sequence if ...
CommunityBot
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Idiomatic F# for iterating a seq and mapping whenever changes occur on a given selection
I've written a function that takes a sequence and check for every item in that sequence whether the current value a selection (obtained with a selection function) is different (or on the first ...
CommunityBot
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N-Queens Puzzle
The N-Queens puzzle can be solved in many ways. One is by a depth-first-search backtracking algorithm.
Below is my generalized version using mutual recursion:
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Advent of Code 2019 day 2 in F#
I sped through the 5hr F# pluralsight course this week-end and thought I'd sement my learning by going through as many Advent of Code puzzles I could with this new learning. However, already on day 2 ...
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Solving the game Set in F#
I was playing the game Set online, and thought it would be a good exercise to write an F# script to find all of the sets for me.
The rules of set are as follows:
A SET is 3 cards for which each ...
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F# Binary Tree and Tree Traversal
So for an side exercise on exercism I implemented a BinarySearchTree.
I was confident in implementing the creation of the binary tree. But I'm very unsure about the traversal of the tree. So I came ...
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Functional Dependency Injection Abstraction
The F# web-development framework Giraffe supports a functional style of Dependency Injection using a form of the Reader monad, as explained in this GitBook. I would like to use this pattern more ...
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Assigning jobs in a functional style
I'm new to F# and functional programming in general (coming from an object oriented background). I just wanted to get some criticism on an algorithm for assigning jobs to crew members. I want to be as ...
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Flashcard Website
In my endeavor to learn Angular, I've created a flashcard site with an F#/Mongo backend. As I'm new to Angular, I'm going to post everything; any and all feedback is welcome.
First, some pictures of ...
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Asp.net middleware [closed]
This code is asp.net core middleware written in f# and called from c# for a blazor server-side app. How can this be made more efficient if any in regards to the async code.
F#:
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Query a product from a list of brands
I am quite new to F# and just wrote my first program. It checks if the query exists in the brand list and returns the matching brand.
Query is the string you are searching for in the brand list. So ...
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Sanitize input for a "robot on a grid" kata
I have the following piece of code which is FSI tested and works.
However, I want to trim it as much as possible (not only the comments, which are there for my own future reference) and make it as ...
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Reading input from console in F# (as a sequence of lines)
Consuming input line-by-line until the end is often useful. In C# I would write the following loop:
while ((line = Console.ReadLine()) != null) {
// ...
I ...
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Hierarchical State Machine in F#
I appreciate any feedback on where I might alter or improve my code for this project. This is an old attempt at implementing a Hierarchical State Machine in F#. I'm from a C#/OO background mostly.
<...
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F# XML Generation in .NET Core: XmlSerializer or XmlProvider
I am working on SEPA XML generator in F#.
I developed two solutions that are roughly equivalent, one relies on the XmlSerializer while the other relies on ...
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Idiomatic way to write proper F# (x)unit + fsunit tests?
I am writing some unit tests using XUnit in F# and I am wondering what is the most idiomatic way in the F# sense to write them.
Let's start a simple case:
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Creation of matrix with specific attempts at the end
What I want to do is build a Slay-the-Spire-like Map. As you can see in the following image, the map is splitted in ISteps and ...
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F#, Timer and propperly removed ElapsedEventHandler
I have a simple method that receives messages from bus, builds response and send it back, and it looks like:
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Asynchronous IBAN API with validation
I am working on an iban api which is about saving the iban of some members after (iban validation) in a database. The code is split between Domain (entities, behaviour for iban validation), Database ...
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A* Algorithm in F#
Inspired by this post I looked up A* on wikipedia and went on with my own implementation as seen below where I try to mimic the pseudocode on Wikipedia but in a recursive manner.
I would like any ...
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