Class: Reality::List

Inherits:
Array
  • Object
show all
Defined in:
lib/reality/list.rb

Overview

List is subclass of Array, which allows effective entities storing and loading.

You can create list from entities or just their names:

Reality::List.new('Argentina', 'Ukraine')
# => #<Reality::List[Argentina?, Ukraine?]>

...or from existing entities:

Reality::List.new(Reality::Entity.new('Argentina'), Reality::Entity.new('Ukraine'))
# => #<Reality::List[Argentina?, Ukraine?]>

List is useful for compact inspect (see above), and for effective batch loading (see #load!).

Also, List is smart enough to remain List on multiple enumerable methods like #select, #reject, #map and so on:

Reality::List.new('Argentina', 'Bolivia', 'Chile').sample(2)
# => #<Reality::List[Chile?, Argentina?]>

Reality::List.new('Argentina', 'Bolivia', 'Chile').load!.map(&:capital)
# => #<Reality::List[Buenos Aires?, La Paz?, Santiago?]>

Instance Method Summary collapse

Constructor Details

#initialize(*names) ⇒ List

Creates List from a set of entity names or entity objects. Also aliased as Reality::List() method.



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# File 'lib/reality/list.rb', line 39

def initialize(*names)
  super names.map(&method(:coerce))
end

Instance Method Details

#describe ⇒ nil

Prints compact description of the list. Implicitly loads all list if not loaded.

Reality::List.new('Argentina', 'Bolivia', 'Chile').describe
# -------------------------
# #<Reality::List(3 items)>
# -------------------------
#   keys: adm_divisions (3), area (3), calling_code (3), capital (3), continent (3), coord (3), country (3), created_at (3), currency (3), gdp_nominal (3), gdp_ppp (3), head_of_government (2), head_of_state (3), highest_point (3), iso2_code (3), iso3_code (3), long_name (3), neighbours (3), official_website (1), organizations (3), part_of (3), population (3), tld (3), tz_offset (3)
#  types: country (3)



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# File 'lib/reality/list.rb', line 85

def describe
  load! unless all?(&:loaded?)
  
  meta = {
    types: map(&:wikipedia_type).compact.map(&:symbol).
      group_count.sort_by(&:first).map{|t,c| "#{t} (#{c})"}.join(', '),
     keys: map(&:values).map(&:keys).flatten.
      group_count.sort_by(&:first).map{|k,c| "#{k} (#{c})"}.join(', '),
  }
  # hard to read, yet informative version:
  #keys = map(&:values).map(&:to_a).flatten(1).
        #group_by(&:first).map{|key, vals|
          #values = vals.map(&:last)
          #[key, "(#{values.compact.count}) example: #{values.compact.first.inspect}"]
        #}.to_h
  puts Util::Format.describe("#<#{self.class.name}(#{count} items)>", meta)
end

#inspect ⇒ String 



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# File 'lib/reality/list.rb', line 68

def inspect
  "#<#{self.class.name}[#{map{|e| e ? e.to_s? : e.inspect}.join(', ')}]>"
end

#load! ⇒ self

Loads all entities in batch. Optimized to make as few requests as possible. Typically, when you want to load several entities



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# File 'lib/reality/list.rb', line 47

def load!
  compact.partition(&:wikidata_id).tap{|wd, wp|
      load_by_wikipedia(wp)
      load_by_wikidata(wd)
    }
  # try to fallback to labels:
  compact.reject(&:loaded?).tap{|entities|
    load_by_wikidata_labels(entities)
  }
  
  self
end