reachlocal/ruby-style-guide — pull request #1 by russCloak (2014-09-30 00:38:53+00:00)
Title: Add rule to favor interpolation over concatenation

Strings should not be concatenated, and instead be assembled with
interpolation. Technically, it is faster for ruby to process because
interpolation modifies the one string, and concatenation creates a new
string from the two being added - then points to the new one.