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Решение на Втора задача от Живко Чобанов

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Резултати

  • 6 точки от тестове
  • 0 бонус точки
  • 6 точки общо
  • 11 успешни тест(а)
  • 0 неуспешни тест(а)

Код

class Collection
include Enumerable
attr_accessor :songs
def initialize(songs = [])
@songs = songs
end
def each(&block)
@songs.each &block
end
def names
@songs.map(&:name).uniq
end
def artists
@songs.map(&:artist).uniq
end
def albums
@songs.map(&:album).uniq
end
def self.parse(text)
new_collection = Collection.new
text.split("\n").select { |line| !line.empty? }.each_slice(3) do |song_data|
new_collection.songs << Song.new(song_data)
end
new_collection
end
def filter(criteria)
Collection.new @songs.select { |song| criteria.is_satisfied.(song) }
end
def adjoin(other_collection)
Collection.new(@songs + other_collection.songs)
end
end
class Criteria
attr_accessor :is_satisfied
def initialize(&is_satisfied)
@is_satisfied = is_satisfied
end
def create(attribute_name, needle)
@is_satisfied = ->(song) { needle == song.send(attribute_name) }
self
end
def self.name(name)
Criteria.new.create :name, name
end
def self.artist(artist)
Criteria.new.create :artist, artist
end
def self.album(album)
Criteria.new.create :album, album
end
def &(other)
Criteria.new do |song|
@is_satisfied.(song) and other.is_satisfied.(song)
end
end
def |(other)
Criteria.new do |song|
@is_satisfied.(song) or other.is_satisfied.(song)
end
end
def !
Criteria.new { |song| !@is_satisfied.(song) }
end
end
class Song
attr_reader :name, :artist, :album
def initialize( attributes )
@name, @artist, @album = attributes
end
end

Лог от изпълнението

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Finished in 0.01504 seconds
11 examples, 0 failures

История (2 версии и 3 коментара)

Живко обнови решението на 29.10.2012 11:15 (преди над 11 години)

+class Collection
+ include Enumerable
+
+ attr_accessor :songs
+
+ def initialize
+ @songs = []
+ end
+
+ def each(&block)
+ @songs.each &block
+ end
+
+ def names
+ @songs.map(&:name).uniq
+ end
+
+ def artists
+ @songs.map(&:artist).uniq
+ end
+
+ def albums
+ @songs.map(&:album).uniq
+ end
+
+ def self.parse(text)
+ new_collection = Collection.new
+ text.split("\n").select { |line| !line.empty? }.each_slice(3) do |song_data|
+ new_collection.songs << Song.new(song_data)
+ end
+ new_collection
+ end
+
+ def filter(criteria)
+ new_collection = Collection.new
+ new_collection.songs = @songs.select { |song| criteria.is_satisfied.(song) }
+ new_collection
+ end
+
+ def adjoin(other_collection)
+ new_collection = Collection.new
+ new_collection.songs = @songs + other_collection.songs
+ new_collection
+ end
+end
+
+
+class Criteria
+ attr_accessor :is_satisfied
+
+ def create(attribute_name, needle)
+ @is_satisfied = ->(song) { needle == song.send(attribute_name) }
+ self
+ end
+
+ def self.name(name)
+ Criteria.new.create :name, name
+ end
+
+ def self.artist(artist)
+ Criteria.new.create :artist, artist
+ end
+
+ def self.album(album)
+ Criteria.new.create :album, album
+ end
+
+ def &(other)
+ new_criteria = Criteria.new
+ new_criteria.is_satisfied = lambda do |song|
+ @is_satisfied.(song) and other.is_satisfied.(song)
+ end
+ new_criteria
+ end
+
+ def |(other)
+ new_criteria = Criteria.new
+ new_criteria.is_satisfied = lambda do |song|
+ @is_satisfied.(song) or other.is_satisfied.(song)
+ end
+ new_criteria
+ end
+
+ def !
+ new_criteria = Criteria.new
+ new_criteria.is_satisfied = ->(song) { !@is_satisfied.(song) }
+ new_criteria
+ end
+end
+
+
+class Song
+ attr_reader :name, :artist, :album
+
+ def initialize( attributes )
+ @name, @artist, @album = attributes
+ end
+end
new_collection = Collection.new

new_collection.songs = @songs + other_collection.songs

new_collection

Това ме дразни - мога ли някак да избегна въвеждането на променливата new_collection или, като променям songs, да връщам обекта, а не променения му атрибут, т.е. new_collection.songs = ... да връща new_collection, а не new_collection.songs ?

Живко обнови решението на 29.10.2012 13:31 (преди над 11 години)

class Collection
include Enumerable
attr_accessor :songs
- def initialize
- @songs = []
+ def initialize(songs = [])
+ @songs = songs
end
def each(&block)
@songs.each &block
end
def names
@songs.map(&:name).uniq
end
def artists
@songs.map(&:artist).uniq
end
def albums
@songs.map(&:album).uniq
end
def self.parse(text)
new_collection = Collection.new
text.split("\n").select { |line| !line.empty? }.each_slice(3) do |song_data|
new_collection.songs << Song.new(song_data)
end
new_collection
end
def filter(criteria)
- new_collection = Collection.new
- new_collection.songs = @songs.select { |song| criteria.is_satisfied.(song) }
- new_collection
+ Collection.new @songs.select { |song| criteria.is_satisfied.(song) }
end
def adjoin(other_collection)
- new_collection = Collection.new
- new_collection.songs = @songs + other_collection.songs
- new_collection
+ Collection.new(@songs + other_collection.songs)
end
end
class Criteria
attr_accessor :is_satisfied
+ def initialize(&is_satisfied)
+ @is_satisfied = is_satisfied
+ end
+
def create(attribute_name, needle)
@is_satisfied = ->(song) { needle == song.send(attribute_name) }
self
end
def self.name(name)
Criteria.new.create :name, name
end
def self.artist(artist)
Criteria.new.create :artist, artist
end
def self.album(album)
Criteria.new.create :album, album
end
def &(other)
- new_criteria = Criteria.new
- new_criteria.is_satisfied = lambda do |song|
+ Criteria.new do |song|
@is_satisfied.(song) and other.is_satisfied.(song)
end
- new_criteria
end
def |(other)
- new_criteria = Criteria.new
- new_criteria.is_satisfied = lambda do |song|
+ Criteria.new do |song|
@is_satisfied.(song) or other.is_satisfied.(song)
end
- new_criteria
end
def !
- new_criteria = Criteria.new
- new_criteria.is_satisfied = ->(song) { !@is_satisfied.(song) }
- new_criteria
+ Criteria.new { |song| !@is_satisfied.(song) }
end
end
class Song
attr_reader :name, :artist, :album
def initialize( attributes )
@name, @artist, @album = attributes
end
end