Class: Array

Inherits:
Object
  • Object
show all
Defined in:
lib/enumerable/extra.rb

Instance Method Summary collapse

Instance Method Details

#map(method = nil, *args, &block) ⇒ Object Also known as: collect

Returns a new array containing the results of running block once for every element in the array.

Examples:

array = ['foo', 'bar']

# No arguments
array.map(:capitalize) => ['Foo', 'Bar']

# With arguments
array.map(:+, 'x') => ['foox', 'barx']

# With arguments and a block
array.map(:capitalize){ |e| e + 'x' } => ['Foox', 'Barx']

Note that for 1.9.x users, Enumerator objects are converted explicitly back into arrays. – The Array class actually has its own implementation of the map method, hence the duplication.



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# File 'lib/enumerable/extra.rb', line 98

def map(method=nil, *args, &block)
   if method
      array  = []
      method = method.to_sym unless method.is_a?(Symbol)

      each{ |obj|
         temp = obj.send(method, *args)
         if block
            array << block.call(temp)
         else
            array << temp
         end
      }

      RUBY_VERSION.to_f >= 1.9 ? array.to_a : array
   else
      RUBY_VERSION.to_f >= 1.9 ? old_map(&block).to_a : old_map(&block)
   end
end

#map!(method = nil, *args, &block) ⇒ Object Also known as: collect!

Same as Array#map, but modifies the receiver in place. Also note that a block is not required. If no block is given, an array of values is returned instead



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# File 'lib/enumerable/extra.rb', line 122

def map!(method=nil, *args, &block)
   self.replace(map(method, *args, &block))
end

#old_map ⇒ Object

These methods are defined separately in array.c, and they are not actual aliases, so we must alias them each separately from Enumerable.



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# File 'lib/enumerable/extra.rb', line 71

alias old_map map

#old_map! ⇒ Object 



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# File 'lib/enumerable/extra.rb', line 72

alias old_map! map!