Issue #19015 has been updated by pyromaniac (Arkadiy Zabazhanov). Hey folks. I'm actually wondering, why don't support Elixir-like sigils in Ruby? We have a ton of them already: `%w[]`, `%r//`, so why don't just add a support for custom ones? I'm, for once, time of writing `Date.new` or `Time.parse`, I'd like to have it `%D[2023-05-05]` or Money gem can introduce something like `%M[100 USD]` instead of the long `Money.from_amount(100, "USD")` version. ---------------------------------------- Feature #19015: Language extension by a heredoc https://bugs.ruby-lang.org/issues/19015#change-102972 * Author: ko1 (Koichi Sasada) * Status: Open * Priority: Normal ---------------------------------------- This propose new heredoc extension with `<<!LANG` like ```ruby doc = <<!LANG # description written in lang LANG foo bar LANG ``` and it is translated to: ```ruby doc = heredoc_extension_LANG(heredoc_text, binding) ``` ## Example ```ruby require 'erb' def heredoc_extension_erb str, b ERB.new(str).run(b) end name = 'ko1' html = <<!erb <div>Hello <%= name %></div> erb puts html #=> <div>Hello ko1</div> ``` ## Background / considerations * Sometimes we write Ruby syntax string with `<<RUBY` and this proposal inspired by it. * it is similar to shebang (`#!LANG` in shell) * [Elixir's custom sigil](https://elixir-lang.org/getting-started/sigils.html) translates `~u(...)` translates to `sigil_u(...)`. This is why it translated to `heredoc_extension_LANG(...)` private method call. * JavaScript has JSX but I don't think it is fit to the Ruby language. * Heredoc is Ruby's chaos part and already confusing a lot. Additional chaos doesn't matter. * `<<!foo` is valid syntax but now I don't think it is not used. gem codesearch doesn't find the usage. * Sorry I couldn't wait 1st/Apr. ## Implementation I attached the experimental implementation which only supports `erb` (because I couldn't find how to get delimiter to determine a method name :p). ---Files-------------------------------- heredoc_extension.patch (2.7 KB) -- https://bugs.ruby-lang.org/