aycabta

RubyKaigi 2021

Hello, everyone. My name is Itoyanagi. I'm a climber, in particular, I do a lot of sawanobori. It is said that "the best way to enjoy the mountains is Sawanobori," so I wade through rapids in the wilderness, climb waterfalls, sometimes procure food locally, sleep by the fire, and head for the headwaters.

I was supposed to give a technical presentation on the riverside, as I always do in my online presentations, but I couldn't make it at all. So, I just spliced together some random footage from some mountains, and overlaid a technical explanation on top of it.

First of all, let me explain what the schedule was like this time. When I was accepted to RubyKaigi, I hadn't implemented any of the accepted features. This is a rough technique called "Kaigi Driven Development" that Ruby committers often use to make progress by taking advantage of the fact that they will have to implement the content to present it. The deadline for submitting videos for this year's English presentation was August 31s

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RDoc with frozen_string_literal

# use Ruby 2.4.3
$ ruby -v
ruby 2.4.3p205 (2017-12-14 revision 61247) [x86_64-linux]

# source code of Ruby 2.4.3
$ find . -maxdepth 1 -name "ruby-2.4.3"
./ruby-2.4.3

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# Reads unified diff file of CRuby documents between "before" and "after"
# from standard input and removes fixed line number changes

class MyRemover
  def initialize
    @lines = STDIN.readlines
    @pos = 0
    puts read_file_sections.flatten.join
  end

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#!/bin/bash

if [ $# -ne 1 ]; then
        echo 'Usage: ./doctest.sh username/repository'
        exit -1
fi
GITHUB_REPOSITORY_PATH=$1
GITHUB_USERNAME=`echo $GITHUB_REPOSITORY_PATH | sed -e 's/\/.\+$//'`

if [ ! -d original-rdoc ]; then

aycabta

all: freebsd_pwm

freebsd_pwm: freebsd_pwm.o
        clang freebsd_pwm.o -o freebsd_pwm

freebsd_pwm.o: freebsd_pwm.c
        clang -c freebsd_pwm.c

clean:
        rm freebsd_pwm freebsd_pwm.o

aycabta

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>                                                                                                                

#include <sys/gpio.h>

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all: test

test: test.o
        gcc bcm2835-1.50/src/bcm2835.o test.o -o test

test.o: test.c
        gcc -c -Ibcm2835-1.50/src/ test.c

clean:
        rm test test.o

aycabta

require 'mechanize'

EMAIL = ''
PASSWORD = ''

agent = Mechanize.new
agent.user_agent = 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36'
puts 'log in try...'
page = agent.get('https://www.amazon.co.jp/')
signin_path = page.search('script').map(&:text).select { |t| t.include?('nav-flyout-ya-signin') }.first.gsub(/^.+nav-flyout-ya-signin[^>]+><a href='([^']+)'.+$/m, '\1')

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require 'libusb'

VENDOR_ID = 0x0922
PRODUCT_ID = 0x8003
SCALING_FACTOR = 0.1

usb_context = LIBUSB::Context.new
device = usb_context.devices(idVendor: VENDOR_ID, idProduct: PRODUCT_ID).first
unless device
  puts 'Device not found'

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require 'open-uri'
require 'json'

open('https://raw.githubusercontent.com/github/gemoji/master/db/emoji.json') do |f|
  json = JSON.parse(f.read)
  puts json.size # => 1338
end