module Browser

Browser.modern_rules << -> b { b.chrome? && b.version >= "37" }
Browser.modern_rules.clear
# Only Chrome Canary is considered modern.

To redefine all rules, clear the existing rules before adding your own.

=== and accepts the browser object.
A rule must be a proc/lambda or any object that implements the method
Define the rules which define a modern browser.

def self.modern_rules
  @modern_rules ||= []
end