Ruby refinements: Difference between revisions
From wikinotes
Line 21: | Line 21: | ||
module Passenger | module Passenger | ||
refine User | refine User | ||
def buckle_seatbelt; end | def buckle_seatbelt; end # method added to 'User' instances if 'using Passenger' | ||
end | end | ||
end | end | ||
Line 27: | Line 27: | ||
<syntaxhighlight lang="ruby"> | <syntaxhighlight lang="ruby"> | ||
# | # has_refinement.rb | ||
using Passenger # User instances gain 'buckle_seatbelt' -- but only in this file | using Passenger # User instances gain 'buckle_seatbelt' -- but only in this file | ||
Line 35: | Line 35: | ||
<syntaxhighlight lang="ruby"> | <syntaxhighlight lang="ruby"> | ||
# | # ./no_refinement.rb | ||
user = User.new | user = User.new | ||
user.buckle_seatbelt # raises exception -- 'buckle_seatbelt not defined' | user.buckle_seatbelt # raises exception -- 'buckle_seatbelt not defined' | ||
</syntaxhighlight> | </syntaxhighlight> | ||
</blockquote><!-- Example --> | </blockquote><!-- Example --> |
Revision as of 15:28, 14 May 2022
Refinements let you limit the scope of Monkey-Patches.
You can override methods, or add new ones, and they will only be applied to classes/modules in files where the refinement is used.
Documentation
official docs https://docs.ruby-lang.org/en/3.0.0/doc/syntax/refinements_rdoc.html
Example
class User def firstname; end def lastname; end end module Passenger refine User def buckle_seatbelt; end # method added to 'User' instances if 'using Passenger' end end# has_refinement.rb using Passenger # User instances gain 'buckle_seatbelt' -- but only in this file user = User.new user.buckle_seatbelt# ./no_refinement.rb user = User.new user.buckle_seatbelt # raises exception -- 'buckle_seatbelt not defined'