2017.09.15 週刊Railsウォッチ（20170915）Ruby 2.4.2リリースで脆弱性修正、strong_migrations gemでマイグレーションチェック、書籍『Mastering PostgreSQL』ほか こんにちは、hachi8833です。Macbook Proの底のゴムが4つとも取れてしまったので、障子の滑りをよくするスライドクッション（ホームセンターで270円）を貼ってみたらすごく具合がよくてうれしい今日この頃です。なおGenius Barでのゴム修復の見積は1万2000円でした。 それでは今週のウォッチ、いってみましょう。 臨時ニュース: Ruby 2.4.2リリース: 脆弱性修正を含む 公式: Ruby 2.4.2 リリース 差分: v2_4_1...v2_4_2 脆弱性の修正箇所を差分から追おうとしたのですが、CVE番号とかがコミットメッセージに見つから
In Ruby, there are many methods available which help us to modify a float or integer value. Ruby 2.3.x In the previous versions of Ruby, we could use methods such as floor, ceil and truncate in following ways. 5.54.floor #=> 5 5.54.ceil #=> 6 5.54.truncate #=> 5 Providing an argument to these methods would result in ArgumentError exception. Ruby 2.4 Ruby community decided to come up with an option
In Ruby, we commonly use uniq method on an array to fetch the collection of all unique elements. But there may be cases where we might need elements in a hash by virtue of uniqueness of its values. Let's consider an example of countries that have hosted the Olympics. We only want to know when was the first time a country hosted it. # given object { 1896 => 'Athens', 1900 => 'Paris', 1904 => 'Chica
Ruby 2.4 got released this Christmas with a lot of exciting features. One of the most underrated features in ruby 2.4 is hash table improvements. Before going into details about implementation, let’s first check the benchmark to know how this change gonna affect your ruby application. Some benchmarks are: Getting keys and values of a hash h = {} 10000.times do |i| h[i] = nil end # Get all hash val
fill(val) -> self[permalink][rdoc][edit] fill {|index| ... } -> self すべての要素に val をセットします。 このメソッドが val のコピーでなく val 自身をセットすることに注意してください。 val の代わりにブロックを指定するとブロックの評価結果を値とします。 [PARAM] val: 自身にセットしたいオブジェクトを指定します。 例 a = [0, 1, 2, 3, 4] a.fill(10) p a #=> [10, 10, 10, 10, 10] a = [0, 1, 2, 3, 4] a.fill("a") p a #=> ["a", "a", "a", "a", "a"] a[0].capitalize! p a #=> ["A", "A", "A", "A", "A"] fill(val, star
Resources What is Heroku? Help Customers Careers Events Podcasts Compliance Center Heroku is for Developers CTOs Team Collaboration Startups Enterprises Agencies Students See More Languages Node.js Ruby Java PHP Python Go Scala Clojure See More Latest News from the Heroku Blog Heroku Blog Find out what's new with Heroku on our blog. More news View all blog posts The Ruby maintainers continued thei
In Ruby 2.4, clamp method is added to the Comparable module. This method can be used to clamp an object within a specific range of values. clamp method takes min and max as two arguments to define the range of values in which the given argument should be clamped. Clamping numbers clamp can be used to keep a number within the range of min, max. 1 210.clamp(5, 20) 3=> 10 4 510.clamp(15, 20) 6=> 15 7
There are some articles highlighting new features of the upcoming Ruby 2.4. I decided to run a basic benchmark comparing Ruby 2.4 to Ruby 2.3.3 and was pleasantly surprised. A few weeks ago I wrote about HexaPDF’s performance by running a benchmark that compares HexaPDF to various other tools in regards to optimizing the size of a PDF file. However, with this real-world benchmark I cannot only com
Hello there. Thanks for visiting! My name is Jesus Castello, and I would like to help you become a world-class Ruby developer. If you would like to contact me (I don't bite!) you can find my contact info on the About page. It has become a tradition to release new Ruby versions on Christmas. And in this post I want to cover some of the most interesting changes in the next version so you can keep up
Ruby uses Fixnum class for representing small numbers and Bignum class for big numbers. 1# Before Ruby 2.4 2 31.class #=> Fixnum 4(2 ** 62).class #=> BignumCopy In general routine work we don't have to worry about whether the number we are dealing with is Bignum or Fixnum. It's just an implementation detail. Interestingly, Ruby also has Integer class which is superclass for Fixnum and Bignum. Star
Comma-Separated Values (CSV) is a widely used data format and almost every language has a module to parse it. In Ruby, we have CSV class to do that. According to RFC 4180, we cannot have unescaped double quotes in CSV input since such data can't be parsed. We get MalformedCSVError error when the CSV data does not conform to RFC 4180. Ruby 2.4 has added a liberal parsing option to parse such bad da
Posted by naruse on 9 Nov 2016 Ruby 2.4.0-preview3がリリースされました. これはRuby 2.4.0に向けた3番目のプレビューリリースになります。 プレビューリリースとはRubyコミュニティのフィードバックを得るためにリリースされています。 何かお気づきの際は、Ruby 2.4.0をよりよくするためにRuby バグレポートガイドラインを参考にしてバグレポートや提案を送ってください。 Introduce hash table improvement by Vladimir Makarov 従来Rubyのハッシュテーブルの内部実装 (st_table) ではに双方向連結リストとチェイン法を用いた実装が使われていましたが、挿入順の配列にオープンアドレス法を用いることによる高速化が行われました。 この改善に際しては多くの方による議論が行われ、とりわ
It is a common use case to calculate sum of the elements of an array or values from a hash. 1 2[1, 2, 3, 4] => 10 3 4{a: 1, b: 6, c: -3} => 4 5 Copy 1 2> [1, 2, 3, 4].sum 3 #=> 10 4 5> {a: 1, b: 6, c: -3}.sum{ |k, v| v**2 } 6 #=> 46 7 8> ['foo', 'bar'].sum # concatenation of strings 9 #=> "foobar" 10 11> [[1], ['abc'], [6, 'qwe']].sum # concatenation of arrays 12 #=> [1, "abc", 6, "qwe"] 13 Copy U
リリース、障害情報などのサービスのお知らせ
最新の人気エントリーの配信
j次のブックマーク
k前のブックマーク
lあとで読む
eコメント一覧を開く
oページを開く
