47 lines
1.1 KiB
Ruby
47 lines
1.1 KiB
Ruby
|
class Enum < SimpleDelegator
|
||
|
|
# Public: Initialize an enum.
|
||
|
|
#
|
||
|
|
# members - the array of enum members. May contain a hash of options:
|
||
|
|
# :start - the number of first enum member. Defaults to 1.
|
||
|
|
#
|
||
|
|
# Examples
|
||
|
|
#
|
||
|
|
# FRUITS = Enum.new(:apple, :orange, :kiwi)
|
||
|
|
def initialize(*members)
|
||
|
|
super({})
|
||
|
|
|
||
|
|
options = members.extract_options!
|
||
|
|
start = options.fetch(:start) { 1 }
|
||
|
|
|
||
|
|
update Hash[members.zip(start..members.count + start)]
|
||
|
|
end
|
||
|
|
|
||
|
|
# Public: Access the number/value of member.
|
||
|
|
#
|
||
|
|
# ids_or_value - number or value of member.
|
||
|
|
#
|
||
|
|
# Returns value if number was provided, and number if value was provided.
|
||
|
|
def [](id_or_value)
|
||
|
|
fetch(id_or_value) { key(id_or_value) }
|
||
|
|
end
|
||
|
|
|
||
|
|
# Public: Check if supplied member is valid.
|
||
|
|
def valid?(member)
|
||
|
|
has_key?(member)
|
||
|
|
end
|
||
|
|
|
||
|
|
# Public: Create a subset of enum, only include specified keys.
|
||
|
|
def only(*keys)
|
||
|
|
dup.tap do |d|
|
||
|
|
d.__getobj__.keep_if { |k| keys.include?(k) }
|
||
|
|
end
|
||
|
|
end
|
||
|
|
|
||
|
|
# Public: Create a subset of enum, preserve all items but specified ones.
|
||
|
|
def except(*keys)
|
||
|
|
dup.tap do |d|
|
||
|
|
d.__getobj__.delete_if { |k| keys.include?(k) }
|
||
|
|
end
|
||
|
|
end
|
||
|
|
end
|