Functional programming is a paradigm which attempts to solve computational problems by the chained evaluation of functions whose output is determined by their inputs rather than the program state. In this style of programming, side effects and mutable data are deprecated.
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Clojure function composition: logging results of an action performed by a “pure” function
I'm wondering how I could compose this program better allow it to grow more functionality without constant refactoring.
This is my code sample for Hacker School, so I'm less married to the results ...
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1answer
21 views
Removing duplicates from list and filtering non-letter characters
I'm just starting out in Haskell and have been set an assignment for uni where I have to create a reverse index of words in a text file and find what line numbers they appear on. I also have to remove ...
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1answer
31 views
Counting items in categories
I'm an experienced programmer that also has a little experience with functional programming, although mostly theoretical (as in hobby-level reading and very minor projects).
I recently decided to ...
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2answers
42 views
Curious fractions in functional Ruby
Problem 33 in Project Euler asks:
The fraction 49/98 is a curious fraction, as an inexperienced
mathematician in attempting to simplify it may incorrectly believe
that 49/98 = 4/8, which is ...
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2answers
41 views
Refactor module for calls to internal image service
Looking for help refactoring the following code to follow a Functional Programming paradigm.
The first function builds a configuration object with default settings and optional presets, while the ...
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0answers
18 views
Which one of these both run-length decoding algorithm is the most optimal?
I'm working out on Ocaml.org 99 problems, and I solved the run-length decode one.
Here is the solution given by the site:
...
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1answer
25 views
Aggregation of a collection of object's nested array-properties
Use Case
So our lead programmer loves to follow the NIH Anti-Pattern and consequently I'm not allowed to use Underscore.js and can only use Vanilla JS... and we have to support IE8.
The goal is to ...
6
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1answer
103 views
BBCode to HTML converter using functional programming
I was inspired to write a BBCode to HTML converter as I'm currently learning functional programming. I wanted achieve functional cohesion. jsFiddle
I'd like feedback on:
structuring of the code. ...
2
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2answers
30 views
What do you think about this custom syntax? [closed]
I'm making a programming language and I've got the basis of a virtual machine working. The next step to is design the actual syntax for the language. I'd just like to know if whether the example ...
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2answers
45 views
Decomposing bitfield with Haskell: is recursion the only way to do this?
Here's a program to take a bitfield like 7 and decompose it into the flags [1,2,4].
Ignore that the algorithm for doing this doesn't use bit shifting/is stupid.
Problems: it seems like I have to have ...
6
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2answers
82 views
Package manager in Clojure
I wrote a package manager in clojure that does 5 things:
depend a b //creates a and b (if they don't exist) and adds dependency on a
install a //installs a and its dependencies
list //prints out ...
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0answers
43 views
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3answers
256 views
Java 8 Effective Use of Multiple Streams
I am experimenting with streams and lambdas in Java 8. This is my first serious foray using functional programming concepts; I'd like a critique on this code.
This code finds the Cartesian product of ...
11
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1answer
145 views
Refractoring OOP vs. Functional Programming Approach
I am writing a python script that will call mandrills export activity api for every blog on a worpress mu install except for the main site. The script is designed to be called from a cron job on a ...
6
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1answer
80 views
Functional, but not recursive, tree traversal
To learn tree traversal i implemented os.walk, tail-recursive and stack-based. Unfortunately Python doesn't support tail call optimization. How do i rewrite my ...
2
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1answer
38 views
Loop filling a set with logging
After watching Raymond Hettingers talk Transforming Code into Beautiful, Idiomatic Python I got back to a function I wrote.
I'm not quite sure how to make it more pythonic but I think this might be a ...
6
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1answer
56 views
Monadic Immutable Linked List in the Least Functional Language Evar
I've written a List monad as an example for a related question. This is a rather frustrating experience as I wanted to use Java, which (as of Java 7) still lacks lambda expressions and lacks ...
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0answers
49 views
Review of genetic algorithm code in Erlang
I've written an Erlang implementation of the genetic algorithm for a hello world program described here: http://www.puremango.co.uk/2010/12/genetic-algorithm-for-hello-world/
This is my first time ...
5
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1answer
49 views
Conversion from decimal to negabinary and vice versa in Haskell
Recently I set about to writing conversion functions in Haskell between decimal and negabinary. I tried to write them in as much functional a style as possible, also aiming at brevity. Below I present ...
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3answers
140 views
Better way to write this code in functional manner using map and reduce?
I have an array of items on which I have to perform 2 tasks:
Applying a function on the array item
Checking if the value is true or false.
The functional approach to solving this would be
...
4
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1answer
50 views
Good OCaml style
I wanted to write a small but non-trivial function in OCaml to test my understanding. I have only a basic understanding of the libraries, and no idea at all of what is considered good style. The ...
5
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1answer
96 views
Read text from stream char by char
I've started learning F# and functional programming in general, but the code I wrote doesn't seems to be really functional. Could you take a look and say how to make it more as it should be in ...
6
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4answers
223 views
Functional approach to splitting list into sub lists
Here is my functional approach to split a list into sub lists, each having non-decreasing numbers, so the input
\$[1; 2; 3; 2; 4; 1; 5;]\$
computes to
\$[[1; 2; 3]; [2; 4]; [1; 5]]\$
The code ...
2
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1answer
79 views
Filtering a dictionary by subject of definitions
I am writing a function to filter a "dictionary" by the "subject" of its definitions.
The dictionary data structure is a hash-map of this kind:
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1answer
119 views
(How) should I avoid writing procedural code in Haskell?
I'm trying to implement a left leaning red black tree as described here. This is their snippet for insert
...
6
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1answer
147 views
Reading input from the console in F#
In the process of learning F#, I wrote this code that reads lines of input from the console and stores them in a list.
As far as I can tell the code works correctly, but since I'm new to functional ...
3
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0answers
66 views
Elixir pipes and anonymous functions
I recently got started with Elixir. I'm used to F#'s pipes, and Seq.map and LINQ's .Select statements. Things are different in ...
2
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1answer
71 views
Functional Re-Write in Scala: Rows of Strings with a Max Width
I came across an issue the other day where I really just could not think of a functional solution. So I fell back on my imperative programming skills. Since a functional solution still eludes me, I ...
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1answer
82 views
Centroid of a polygon in Clojure
I am studying Clojure and functional programming. I wrote this function to compute the centroid of a polygon specified as a vector of points, e.g. ...
5
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1answer
180 views
Code with many “early returns (exits)” into the functional style
I have some Scala code that uses Internet to authorize a user. Therefore, it can throw Exceptions like IOException in the method.
The original code was written in ...
6
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1answer
701 views
Clojure Neural Network
After reading this article about Neural Networks I was inspired to write my own implementation that allows for more than one hidden layer.
I am interested in how to make this code more idiomatic - ...
2
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2answers
146 views
“Hell Difficulty” Haskell Fast & Hard
I'm a complete neophyte to Haskell with only a smidge of FP experience – I did some Racket programming academically and have written some semi-FP JavaScript professionally, but now I'm trying to learn ...
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0answers
124 views
Review my F# Red Black Tree Implementation [closed]
I have written this implementation for red black tree. I also have some helper methods to verify whether the generated tree is really balanced or not.
Looks good to me.... but I find that most of the ...
3
votes
1answer
77 views
Hangman game background image inefficient?
I'm making a Hangman game and it seems that my code doesn't provide me much freedom with using layouts. I added an image to my JFrame then I added a JPanel to my image which I'm using for all the ...
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1answer
123 views
Review my F# QuickSort Program
OK... last sort of the day and probably the most fun. F# is really awesome.
...
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1answer
104 views
Merge Sort Program
I have written the following program to implement merge sort in F#.
Can you please review this and let me know how can I write this in the most functional way (also most efficient and concise)?
In ...
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2answers
52 views
Review my F# BubbleSort Program
I have written this code for BubbleSort in F#. Can you review and let me know how I can do this in most functional way.
...
2
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1answer
68 views
Using types in F#
I've played with F# for over a year, but I've only recently begun tentatively using it for professional work. I'm concerned that my c-style OOP principles are blinding me to the advantages of a ...
4
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3answers
117 views
Improving F# conditional assignment with match expression
In my code I declared a dictionary to store various counters
let counters = Dictionary<Type, int>()
Later, I need to generate several labels using these ...
6
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1answer
113 views
Better or more idiomatic way to apply a sequence of functions in Haskell
This is one of my Haskell solutions to a variation of the N-Queens problem, where the queens can move like knights in addition to their normal moves. It has been optimized somewhat to avoid ...
6
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1answer
117 views
Monad Transformers in C#
I am working on using monad transformers in C#. I would like to know if the following code I present, shows that I have understood this. I am fairly new to this so any feedback / comments are really ...
4
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1answer
68 views
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1answer
172 views
Generic pure functions memoization
I like to create tools for memoization since it can sometimes be useful. I recently created a generic tool for memoizing pure functions results. Here is an example og how it works:
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0answers
91 views
Optimizing my Quadratic Sieve, with advice on style?
I'm still new to Haskell, and I'd like others' opinions on optimizing my basic quadratic sieve, in addition to feedback on the code's clarity and functional style.
The ...
3
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2answers
265 views
Function that builds dictionary based on lambda params
I've written a method in c# that allows me to do create a dictionary from a passed in object and N lambda expressions that reference that objects properties and methods. It's working the way I want it ...
4
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1answer
183 views
Functional linked list
I'm looking for feedback in general: code correctness, best practices, design patterns; everything you think about this. Is it bad code? Where can it be improved?
I've been implementing functional ...
3
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1answer
268 views
Coding Functional style taking longer time than its Imperative style
I wanted to try out F# so I decided to I converted a library file from c# to f#. I have done that successfully(thanks a you people in stackoverflow). At first I ported the code from c# to f#. Than I ...
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2answers
107 views
More functional approach
I wonder if there is a more "functional" way of implementing something like this:
...
9
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2answers
515 views
“Zip-like” functionality with C++11's range-based for-loop
My goal was to get the following code to work:
...
3
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2answers
256 views
How to rewrite this code in functional way?
My code looks like imperative style code. I want to make my code more functional. How I can rewrite my program so it become functional style code?
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