Module: MoreCoreExtensions::RangeStepValue

Defined in:
lib/more_core_extensions/core_ext/range/step_value.rb

Instance Method Summary collapse

Instance Method Details

#step_value(value) ⇒ Object

Iterates over rng, starting with the beginning of rng, incrementing by the value, and passing that element to the block. Unlike step, step_value invokes the + operator to iterate over the range elements. Unless the end is excluded from the range, the final value of the iteration will always be the end value, even if the increment value goes past the end of the range.

This method has performance benefits over step when working with ranges of Time objects, for example, where step calling succ may be called an inordinate number of times.

t = Time.now.midnight
range = (t - 3.days)..t
range.step_value(1.day) {|x| puts x}

produces:

Tue Dec 14 00:00:00 -0500 2010
Wed Dec 15 00:00:00 -0500 2010
Thu Dec 16 00:00:00 -0500 2010
Fri Dec 17 00:00:00 -0500 2010



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# File 'lib/more_core_extensions/core_ext/range/step_value.rb', line 23

def step_value(value)
  if block_given?
    return if self.begin > self.end

    iter = self.begin
    loop do
      yield iter unless iter == self.end && exclude_end?
      break if iter == self.end
      iter += value
      iter = self.end if iter > self.end
    end

    self
  else
    ret = []
    step_value(value) { |v| ret << v }
    ret
  end
end