Module: SelectBy::CoreExtensions::Array::SelectingBy

Defined in:
lib/select_by/core_extensions/array/selecting_by.rb

Defined Under Namespace

Classes: InvalidArgumentError, InvalidSelectingMethodError

Constant Summary collapse

SELECTING_METHODS = 
[:select, :reject, :detect, :partition, :find_all, :find]

Instance Method Summary collapse

Instance Method Details

#detect_by(hash_or_method = nil, &block) ⇒ Object Also known as: find_by 



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# File 'lib/select_by/core_extensions/array/selecting_by.rb', line 55

def detect_by(hash_or_method = nil, &block)
  array = if hash_or_method.nil?
          self
        else
          selecting_by(:select, hash_or_method, true)
        end

  (block_given? ? array.map(&block) : array).first
end

#partition_by(hash_or_method = nil, &block) ⇒ Object 



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# File 'lib/select_by/core_extensions/array/selecting_by.rb', line 45

def partition_by(hash_or_method = nil, &block)
  array = if hash_or_method.nil?
          [self, []]
        else
          selecting_by(:partition, hash_or_method)
        end

  block_given? ? array.map{|inner_array| inner_array.map(&block)} : array
end

#reject_by(hash_or_method = nil, &block) ⇒ Object

works the same as select_by but returns elements that do not evaluate to true



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# File 'lib/select_by/core_extensions/array/selecting_by.rb', line 41

def reject_by(hash_or_method = nil, &block)
  select_or_reject_by(:reject, hash_or_method, &block)
end

#select_by(hash_or_method = nil, &block) ⇒ Object Also known as: find_all_by

if a hash is provided use each hash key as a method name and value as what the method should return if any of key/value pairs are not callable or do not match the reciever based on equality then reject the element of the array. if argument that is provided is a callable method (calling to_s on the object returns a method the element responds to) then call that method on each element only returning the elements that return a truthy value (similar to select(&:method)).

if you provide a code block the method will apply that code block to each returned element

[“Smith”, “peter”].detect_by(:size => 5) # => “Smith” [“Smith”, “peter”].detect_by(:size => 5, &:downcase) # => “smith”

“Smith”, “peter”].select_by(:size => 5) {|name| name.downcase} # => [“smith”, “peter”
“Smith”, “peter”].reject_by(:size => 5, &:downcase) # => [

when the object does not respond to the key the selecting block assumes it is falsey

“Smith”, “peter”].reject_by(:peter => 5, &:downcase) # => [“smith”, “peter”
“Smith”, “peter”].select_by(:peter => 5, &:downcase) # => [ 


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# File 'lib/select_by/core_extensions/array/selecting_by.rb', line 36

def select_by(hash_or_method = nil, &block)
  select_or_reject_by(:select, hash_or_method, &block)
end