Class: Enumerable::Enumerator

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

Instance Method Summary collapse

Instance Method Details

#next ⇒ Object

call-seq:

e.next   => object

Returns the next object in the enumerator, and move the internal position forward. When the position reached at the end, internal position is rewinded then StopIteration is raised.

Note that enumeration sequence by next method does not affect other non-external enumeration methods, unless underlying iteration methods itself has side-effect, e.g. IO#each_line.

Caution: This feature internally uses Generator, which uses callcc to stop and resume enumeration to fetch each value. Use with care and be aware of the performance loss.

Raises:

  • (StopIteration) 


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# File 'lib/generator.rb', line 188

def next
  g = __generator
  return g.next unless g.end?

  g.rewind
  raise StopIteration, 'iteration reached at end' 
end

#rewind ⇒ Object

call-seq:

e.rewind   => e

Rewinds the enumeration sequence by the next method.



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# File 'lib/generator.rb', line 200

def rewind
  __generator.rewind
  self
end