This is a Ruby tree! It shows every object from the Ruby Programming Language in a tree format.

metadata 

        # Gem::Specification.metadata

(from ruby core)
---

The metadata holds extra data for this gem that may be useful to other
consumers and is settable by gem authors.

Metadata items have the following restrictions:

*   The metadata must be a Hash object
*   All keys and values must be Strings
*   Keys can be a maximum of 128 bytes and values can be a maximum of
    1024 bytes
*   All strings must be UTF-8, no binary data is allowed


You can use metadata to specify links to your gem's homepage, codebase,
documentation, wiki, mailing list, issue tracker and changelog.

    s.metadata = {
      "bug_tracker_uri"   => "https://example.com/user/bestgemever/issues",
      "changelog_uri"     => "https://example.com/user/bestgemever/CHANGELOG.md",
      "documentation_uri" => "https://www.example.info/gems/bestgemever/0.0.1",
      "homepage_uri"      => "https://bestgemever.example.io",
      "mailing_list_uri"  => "https://groups.example.com/bestgemever",
      "source_code_uri"   => "https://example.com/user/bestgemever",
      "wiki_uri"          => "https://example.com/user/bestgemever/wiki"
      "funding_uri"       => "https://example.com/donate"
    }

These links will be used on your gem's page on rubygems.org and must
pass validation against following regex.

    %r{\Ahttps?:\/\/([^\s:@]+:[^\s:@]*@)?[A-Za-z\d\-]+(\.[A-Za-z\d\-]+)+\.?(:\d{1,5})?([\/?]\S*)?\z}

This is MURDOC! A Ruby documentation browser inspired by Smalltalk-80. It allows you to learn about Ruby by browsing through its class hierarchies, and see any of its methods.