text
stringlengths
0
444
If you really need "global" methods, add them to Kernel and make them private.
== Classes & Modules
=== Consistent Classes [[consistent-classes]]
Use a consistent structure in your class definitions.
[source,ruby]
----
class Person
# extend/include/prepend go first
extend SomeModule
include AnotherModule
prepend YetAnotherModule
# inner classes
class CustomError < StandardError
end
# constants are next
SOME_CONSTANT = 20
# afterwards we have attribute macros
attr_reader :name
# followed by other macros (if any)
validates :name
# public class methods are next in line
def self.some_method
end
# initialization goes between class methods and other instance methods
def initialize
end
# followed by other public instance methods
def some_method
end
# protected and private methods are grouped near the end
protected
def some_protected_method
end
private
def some_private_method
end
end
----
=== Mixin Grouping [[mixin-grouping]]
Split multiple mixins into separate statements.
[source,ruby]
----
# bad
class Person
include Foo, Bar
end
# good
class Person
# multiple mixins go in separate statements
include Foo
include Bar
end
----
=== Single-line Classes [[single-line-classes]]
Prefer a two-line format for class definitions with no body. It is easiest to read, understand, and modify.
[source,ruby]
----
# bad
FooError = Class.new(StandardError)
# okish
class FooError < StandardError; end
# ok
class FooError < StandardError
end
----
NOTE: Many editors/tools will fail to understand properly the usage of `Class.new`.
Someone trying to locate the class definition might try a grep "class FooError".
A final difference is that the name of your class is not available to the `inherited`
callback of the base class with the `Class.new` form.
In general it's better to stick to the basic two-line style.
=== File Classes [[file-classes]]
Don't nest multi-line classes within classes.
Try to have such nested classes each in their own file in a folder named like the containing class.