Yuichi Murata mrk21

mrk21 / code

Last active November 26, 2021 05:10

This `code` command is for containers, and it can also execute on terminals other than vscode

	#!/bin/bash

	# This `code` command is for containers, and it can also execute on terminals other than vscode.
	# If you use it, you must execute it after attaching the container in vscode.
	# see: VSCode Remote SSHで別Shellからファイルを開く https://zenn.dev/shirou/articles/vscode-remote-open-file

	export VSCODE_IPC_HOOK_CLI=$(ls -t /tmp/vscode-ipc-*.sock \| head -1)
	CODE=$(ls -t ~/.vscode-server/bin/*/bin/code \| head -1)
	exec ${CODE} $*

mrk21 / lambda-to-funcptr.cpp

Created June 28, 2020 06:51

	#include<type_traits>
	#include<utility>
	#include<iostream>

	template<typename Callable>
	union storage
	{
	storage() {}
	std::decay_t<Callable> callable;
	};

mrk21 / crypto.js

Last active June 5, 2020 21:43

HMAC SHA256 digest of CryptoJS does not match it of OpenSSL, so should use jsSHA instead of CryptoJS.

	const cryptoJsHmacSHA256Digest = (key, data) => {
	const hmac = CryptoJS.HmacSHA256(data, key);
	const buffer = new ArrayBuffer(hmac.sigBytes);
	const dv = new DataView(buffer);
	hmac.words.forEach((v, i) => dv.setInt32(4*i, v, false));

	let digest = '';
	for (let i = 0; i < hmac.sigBytes; i++) {
	digest += String.fromCharCode(dv.getUint8(i));
	}

mrk21 / binary-to-string.js

Created June 5, 2020 21:09

Binary to Binary String

	const data = [ 102222, 4000032 ];
	const buffer = new ArrayBuffer(4 * 2);
	const dv = new DataView(buffer);
	data.forEach((v, i) => dv.setInt32(4 * i, v, false));

	let result = '';
	for (let i = 0; i < 4 * 2; i++) {
	result += String.fromCharCode(dv.getUint8(i));
	}
	console.log(btoa(result))

mrk21 / tailcall_optimization.rb

Created May 21, 2020 06:28

Tail call optimization for Ruby

	# @see [Rubyの末尾呼び出し最適化を試す - Qiita](https://qiita.com/rsnni/items/8f818f2c2da07896fc7e)
	RubyVM::InstructionSequence.compile_option = {
	:tailcall_optimization => true,
	:trace_instruction => false
	}

	RubyVM::InstructionSequence.new(<<-EOS).eval

	def fact(x)
	return 1 if x == 0

mrk21 / redis_lock.rb

Created January 24, 2020 15:10

Locking between multiple Ruby processes by Redis

	class Lock
	def initialize(redis:, key:)
	@redis = redis
	@key = key
	end

	def lock(timeout_sec: 10)
	start = Time.now.to_i
	loop do
	break yield if @redis.setnx(@key, true)

mrk21 / singleton_method_definition.rb

Created January 22, 2020 05:08

Local variables accessible singleton method definition for Ruby

	class Hoge
	def a
	1
	end
	end

	hoge = Hoge.new
	b = 2
	hoge.define_singleton_method(:b){ b }

mrk21 / sleep.js

Created December 10, 2019 11:13

Sleep for JavaScript (>= ES2015)

	const sleep = (msec) => new Promise(resolve => setTimeout(resolve, msec));

	const main = async () => {
	console.log(1);
	await sleep(1000);
	console.log(2);
	await sleep(1000);
	console.log(3);
	await sleep(1000);
	};

mrk21 / app_controllers_hoges_controller.rb

Created October 3, 2019 09:43

Validation on destroying for Rails

	# frozen_string_literal: true

	class HogesController < ApplicationController
	def destroy
	hoge = Hoge.find(params[:id])
	hoge.destroy!
	redirect_to hoges_path
	rescue ActiveRecord::RecordNotDestroyed => e
	flash[:error] = e.record.errors.full_messages.join("\n")
	flash[:error] = 'Destroying failed' if flash[:error].blank?

mrk21 / output_log_for_net_http.rb

Created September 25, 2019 06:00

How to output logs for Net::HTTP

	require 'net/http'

	# @see https://qiita.com/mechamogera/items/d9ea1cf043e976641a23#rails%E3%81%A7%E7%A2%BA%E8%AA%8D%E3%81%99%E3%82%8B%E6%96%B9%E6%B3%95
	class Net::HTTP
	alias :create :initialize

	def initialize(*args)
	logger = ActiveSupport::Logger.new(STDOUT)
	create(*args)
	self.set_debug_output logger