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sub_ext 

        # Pathname.sub_ext

(from ruby core)
---
    sub_ext(p1)

---

Return a pathname with `repl` added as a suffix to the basename.

If self has no extension part, `repl` is appended.

    Pathname.new('/usr/bin/shutdown').sub_ext('.rb')
        #=> #<Pathname:/usr/bin/shutdown.rb>

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.