“Useless Ruby sugar”: Pattern matching (Pt. 1)

This is a part of a blog post series about “useless” (or: controversial) syntax elements that emerged in recent Ruby version. The goal of the series is not to defend (or criticize) the features, but to share a “thought framework” for analysis of their reasons, design, and effect the new syntax has on a code that uses it. See also intro post, and the previos text that covered numbered block arguments.