Racket is an extensible general programming language in the Lisp family.
2
votes
2answers
144 views
Sudoku solver in Racket
I have written following code to solve Sudoku puzzles in Racket (a Scheme/Lisp derivative programming language). Following relatively simple code appears to work but are there any bugs in it or can it ...
3
votes
1answer
120 views
Advent of Code 2016 Day 1 “No Time for a Taxicab”
I already solved it in JavaScript, where I'm more comfortable. I pretty much ported the algorithm from there.
I wanted to try the first Advent of Code puzzle in a new language and I picked Racket.
...
0
votes
2answers
49 views
Highest number in a list with Racket
I am trying to build a function to find the highest number in a list without using the built-in functions of "apply" and "max".
I created the following code:
...
3
votes
1answer
39 views
Simplifying Macro-Generating Racket Macro
I'm trying to write a small macro library in Racket that extends a few of the racket/match functions I use, by printing which clause was expanded.
While this seems ...
3
votes
2answers
54 views
GUI implementation with Racket
I am studying the book Realm of Racket.
On chapter 5, there is a challenge:
Find an image of a locomotive. Create an animation that runs the locomotive
from just past the left margin to just past ...
3
votes
1answer
84 views
Tic-Tac-Toe game with AI
I started learning Racket recently and decide to revisit the problem that introduced me to computer programming: making a Tic-Tac-Toe game with AI.
Here's the code:
...
1
vote
2answers
93 views
Reverse the order of a list in Racket
I am using the SICP book. There is an exercise in which you need to create a function that will receive a list as an argument and return a list with the same elements in a reverse order.
I know there ...
5
votes
1answer
54 views
“Guess My Number” with Racket
I am using the book "Realm of Racket" which was written by the people behind the Racket and Dr. Racket projects. It is a great book based on games, similar to the famous "Land of Lisp".
The first ...
1
vote
0answers
31 views
Implementation of catch test framework in Racket
As an exercise in learning how to use Racket macros I decided to implement a subset of the features in the catch test framework for C++. In particular the catch test framework has a unique feature ...
2
votes
1answer
41 views
Evaluation of e^x with series expansion
My code calculates \$e^x\$ with series expansion. Is there any way to make it shorter and cleaner?
...
7
votes
1answer
235 views
Doge meme generator in Racket
I wrote a doge meme generator in racket some time ago, mainly as a joke, and I would like some criticism about the general style and what could be improved.
Here is how the program output looks :
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1
vote
1answer
58 views
Functional coffee dispenser [closed]
Inspired by this question, I decided to rewrite this code in Scheme, as I'm working through SICP right now. Any feedback welcome.
...
4
votes
1answer
39 views
Introduce bindings for macro user
I'm doing the Racket track on exercism.io and solved the grains exercise:
Write a program that calculates the number of grains of wheat on a chessboard given that the number on each square doubles.
...
2
votes
1answer
182 views
Mutable stack in Racket
I'm learning Racket and have implemented a mutable stack, which is just a bunch of wrappers around an underlying struct containing a size and buffer list (so it's ...
3
votes
1answer
73 views
in-nest-sequence: sequence generator in Racket
in-nest-sequence is a sequence generator that takes a function and an initial value, and the return value of invoking the function on the current value is used as ...
1
vote
2answers
229 views
Project Euler #12 in Racket
Problem here.
It's not exactly the brute force approach but I'm not using any sort of pre-calculated primes table, and I'm definitely not using the coprimality trick shown in the PE pdf. I'm finding ...
6
votes
1answer
358 views
Binero puzzle solver
During my holiday I decided to implement a solver for those puzzles my girlfriend likes to do. They are called Takuzu, but "binero" in Dutch.
The puzzle gives you a grid in which you have to fill in ...
9
votes
2answers
384 views
Number guessing game in Racket
I decided to learn a Lisp-ish language and I am discovering a very weird and new syntax. The obligatory first program, that also uses all the fundamentals, is the number guessing game.
Did I define ...
2
votes
4answers
4k views
Splitting a list in Racket
I am working my way into learning a bit of Scheme (actually, Racket) with the help of a few practical problems to solve. In this case, I want to split a flat list of symbols at a certain delimiter ...
1
vote
2answers
73 views
Solution to Project Euler #1 - multiples of 3 and 5
I have been programming for about ~2 years, and mostly wrote OOP and structural code. Recently, I have decided to pick up a functional programming language, and Haskell being too alien for me, looked ...
3
votes
1answer
103 views
Digit Summing Function
I'm working through the common divisibility tests, and implementing them in Racket. I'm working on divisible by three, for which I thought it'd be nice to keep summing until I got to a single digit (...
3
votes
0answers
152 views
Graphical editor with geometric intersection
If it is possible I would like some comments on the overall style of the program. It feels like I am writing the whole program as one big script and I'm not sure how to break it down into several ...
10
votes
1answer
449 views
WebSocket-based API library in Racket
I've developed a library in (typed) Racket that wraps a WebSocket-based API. The API itself is very simple—it operates via a series of three-letter commands optionally followed by a JSON-encoded ...
1
vote
1answer
71 views
Extracting values from a list
I had already solved this problem, but in an unnecessarily convoluted way that seems too specific. Can this be done better?
From a list:
(8 "layer-name" 10 x1 20 y1 10 x2 20 y2 10 x3 20 y3)
8, ...
5
votes
1answer
176 views
Simple evaluator of Scheme-like expressions in Haskell
This is my first nontrivial Haskell program:
...
3
votes
0answers
132 views
Calculating continued fraction expansions (without requiring arbitrary precision decimals)
I'm writing a program that will compute a continued fraction expansion of a number. I've been learning Racket/Scheme for a few weeks and I wanted to see what I can do better.
Usage: This program ...
2
votes
1answer
651 views
Finding the subsets of a set
I am trying to write a procedure that finds the power set of a list, that is, the set of 2n subsets (where n is the number of elements in the list). I simply quite find all the subsets. I feel my code ...
1
vote
1answer
191 views
Reading/writing null-terminated strings from socket
I need to handle C style ('\0' delimited) strings from/to a socket and came up with this as a first attempt:
...
18
votes
1answer
375 views
Is this IRC bot utility library Racket-y enough?
To help myself learn Racket, I ported a simple JavaScript ircbot module I wrote for Node.js to Racket. The Racket version is built atop the Racket irc package, so ...
2
votes
1answer
690 views
Solving the N-queens puzzle the Racket or Scheme way
My final version is a direct translation from Python. Thanks to build-in support for generator, its speed is almost the same as Python. As I quite like using generator and list comprehension in Python,...
4
votes
2answers
518 views
Converting English Measurements to Metric and vice versa
I finished answering Exercise 3.3.1 of How to Design Programs where:
Exercise 3.3.1. The United States uses the English system of
(length) measurements. The rest of the world uses the metric ...
2
votes
1answer
93 views
6
votes
4answers
449 views
Project Euler 1 (sum of multiples of 3 or 5 under 1000)
I solved this a while ago. In the moment I solved it I was learning Scheme and, well, I still am. I'm not looking at the best solution (I searched for it and coded it already, in Python), what I want ...
2
votes
1answer
331 views
Simplifying Dr.Racket drawing code
I am using Dr.Racket, Intermediate Student with Lambda. I was wondering if there was any way I can simplify this code using any sort of method like lambda, abstraction, map, filter, etc.
...
3
votes
2answers
108 views
Simplifying Dr.Racket alien code
I am using Dr.Racket, Intermediate Student with Lambda. I was wondering if there was any way I can simplify this code using any sort of method like lambda, abstraction, map, filter, etc.
...
4
votes
2answers
375 views
Why is this RC4 code in Racket so slow?
According to shootout.alioth.debian.org, Racket is not much slower than C#, at least in the same order of magnitude due to its JIT compiler.
However, I'm seeing at least two degrees of magnitude ...
1
vote
0answers
103 views
Creating an updating hash table
I'm not sure if this implementation is good enough. The function takes a vector of 1 million chars and creates a table of the sequences that pass before the next occurrence of itself.
Some questions ...
4
votes
0answers
250 views
Quick Insert Merge Sort
I have written this code to sort a list of numbers, in increasing order.
It is a combination of quick sort, insertion sort, and merge sort. I make the first element of the list a pivot, then I go ...
3
votes
1answer
700 views
Scheme/Racket: idiomatic infix math evaluator
Inspired by xkcd and a couple of praising blog posts, I decided to try out Lisp. It seemed that the best-supported dialect was Racket, itself a variant of Scheme, so I went with that and wrote an ...
6
votes
1answer
598 views
Improving a priority queue sketch in Racket/Scheme
I just put together the skeletons for a priority queue using a binary heap in racket/scheme. Using racket/scheme is all about the educational experience and I was wondering if anyone wants to ...
3
votes
1answer
293 views
A Simple Unix Filter in Racket - Learning the Racket Way
I've written the following simple filter in Racket as my first Racket program and am wondering if I am writing it in an "idiomatic Racket style".
...
5
votes
2answers
944 views
Insert-everywhere function
This is HtDP Excercise 12.4.2:
Develop a function insert-everywhere. It consumes a symbol and a list
of words. The result is a list of words like its second argument, but
with the first ...
2
votes
1answer
702 views
In-nested sequence generator for Racket scheme
I've been learning about Racket sequences and noticed a hole where nested iteration is concerned. We have the in-parallel construct but no ...
