如何用ri查询Ruby核心文档（如Array#join）并在浏览器显示HTML内容？

Since your Ruby 2.4.3 installed via rbenv doesn’t support the -f html flag for ri, here are three reliable ways to get that clean, browser-friendly documentation view:

1. Use YARD (Recommended) #

YARD is a popular Ruby documentation tool that generates beautiful HTML docs, and it works great with older Ruby versions like 2.4.3. Here’s how to set it up:

• First, install YARD in your rbenv Ruby 2.4.3 environment:

  gem install yard
  

• Generate the core Ruby library docs:

  yardoc --ruby-core
  

• Start a local preview server to browse the docs:

  yard server
  

• Open your browser and go to http://localhost:8808 — you’ll find the Array#join documentation under the Array class, formatted with a clean, modern layout.

2. Generate HTML Docs with RDoc #

Since ri is built on RDoc, you can use RDoc directly to generate HTML files for the core docs:

• Ensure RDoc is up to date (Ruby 2.4.3 includes it by default, but updating won’t hurt):

  gem install rdoc
  

• Generate the HTML docs and save them to a directory of your choice (e.g., ~/ruby-core-docs):

  rdoc --all --ri-site --op ~/ruby-core-docs
  

• Once the command finishes, navigate to the output directory and open index.html in your browser. You can easily find Array#join by searching for the Array class.

3. Quick-and-Dirty: Convert ri Output to HTML (For One-Off Queries) #

If you just need to view a single method’s docs quickly, you can pipe ri output to a tool like Pandoc to convert it to HTML:

• Install Pandoc (most package managers have it: brew install pandoc on macOS, sudo apt install pandoc on Debian/Ubuntu)
• Run this command to generate an HTML file for Array#join:

  ri Array#join | pandoc -f markdown -t html > array_join.html
  

• Open array_join.html in your browser — the formatting won’t be as polished as YARD/RDoc, but it’s a fast way to get a readable version.

内容的提问来源于stack exchange，提问作者user9003943