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@Qqwy
Qqwy / YCombinator.ex
Last active January 7, 2022 20:43
Explanation of using the Y-Combinator and wrapping functions in Elixir to write recursive functions and wrap them with extra functionality
defmodule YCombinator do
@moduledoc """
Some functions explaining the Y-Combinator.
Can definitely be improved upon, but this is as much as time allowed me this evening.
"""
def factorial(n) do
y_combinator(&almost_factorial/1).(n)
*> Compile using GNU Cobol, e.g.: `cobc -x gcd_maxmin.cob`
IDENTIFICATION DIVISION.
PROGRAM-ID. gcd-maxmin.
ENVIRONMENT DIVISION.
DATA DIVISION.
WORKING-STORAGE SECTION.
01 NUMS.
05 NUMS-ELEMS PIC 9(9)
OCCURS 0 TO 9999 TIMES DEPENDING ON NUMS-LEN.
77 NUMS-IDX PIC 9(9) COMP.
@Qqwy
Qqwy / caesar_cipher.pl
Created November 9, 2020 21:53
A simple substitution (Caesar/Vernam) cypher, implemented in Prolog. Beginner code; can probably be significantly improved
-module(caesar_cipher, [
shift_plaintext_cyphertext/3,
shift_plainchar_cypherchar/3,
shift_plainletter_cypherletter/3
]).
:- use_module(library(reif)).
:- use_module(library(clpz)).
:- use_module(library(lists)).
@Qqwy
Qqwy / addition.beam_disasm.ex
Last active July 8, 2020 14:34
An example of what BEAM code ends up being generated for a simple TypeCheck spec.
{:beam_file, Addition,
[
{:__info__, 1, 2},
{:"__type_check_spec_for_add/2__", 0, 18},
{:add, 2, 8},
{:baseline_add, 2, 16},
{:module_info, 0, 20},
{:module_info, 1, 22}
], [vsn: [337339698024769425821845159222917769638]],
[
@Qqwy
Qqwy / capturepipe3.ex
Last active June 24, 2020 15:40
Elixir example of a pipe-operator that uses some simple metaprogramming to allow piping into capture-syntax. Version with slightly more verbose `&`-prefixed syntax. Implementation that rewrites pipes nested inside &.
defmodule Capturepipe do
@doc """
A pipe-operator that extends the normal pipe
in one tiny way:
It allows the syntax of having a bare `&1` capture
to exist inside a datastructure as one of the pipe results.
This is useful to insert the pipe's results into a datastructure
such as a tuple.
@Qqwy
Qqwy / capturepipe2.ex
Last active June 24, 2020 15:38
Elixir example of a pipe-operator that uses some simple metaprogramming to allow piping into capture-syntax. Version with slightly more verbose `&`-prefixed syntax. Naive implementation that does not allow using multiple captures in the same pipeline.
defmodule Capturepipe do
@doc """
A pipe-operator that extends the normal pipe
in one tiny way:
It allows the syntax of having a bare `&1` capture
to exist inside a datastructure as one of the pipe results.
This is useful to insert the pipe's results into a datastructure
such as a tuple.
@Qqwy
Qqwy / elixir_operator_info.exs
Created July 7, 2016 20:01
Elixir Operator Info
# See https://github.com/elixir-lang/elixir/blob/master/lib/elixir/src/elixir_parser.yrl#L52
# for the list of operators with associativity, etc.
# The operators in this list are grouped by precedence, low to high.
# The comments indicate the operator's normal function, as well as its ability to be defined/overridden.
-> # CompileError 'unhandled operator'. only allowed in anonymous function syntax.
& # CompileError, only allowed in short anonymous function syntax.
#include <iostream>
#include <vector>
auto continuation = [](auto && val){return [=](auto && cont) { return cont(val);};};
auto style = [](const auto &val) { return val; };
auto mod = [](auto &&modv) { return [=](auto &&truecont){ return [=](auto &&falsecont) { return [=](auto &&val) { if (val % modv) { return truecont(val); } else { return falsecont(val); }; }; }; }; };
auto passing = [](auto &&val) { return [=](auto &&cont){ return [=](auto &&) {return cont(val);};};};
bool isLeapYear(int year){
return (continuation)
{-# LANGUAGE DataKinds, KindSignatures, TypeFamilies, PolyKinds, GADTs #-}
module Example where
import qualified Control.Arrow
import qualified Prelude
import Prelude hiding (id, (.))
import qualified Control.Category
-- | Example type: A Qfun is a function with a Quality: Either 'Good' or 'Bad'.
function base64ImageUploader(dialog) {
var reader, image_url, img;
var canvas = document.createElement("canvas");
var canvas_context = canvas.getContext('2d');
function rotateImage(direction){
//These are swapped when rotating