Class: Integer

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

Instance Method Summary collapse

Instance Method Details

#to_base34 ⇒ Object

Turn a base10 integer into a base34 string representation.

The basic methodology is to decompose work into multiples of 34 - we create the base34 number by taking base34 chunks away from the base10 number.



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# File 'lib/user_friendly_id/integer.rb', line 7

def to_base34
  # our storage string...
  base34_str = String.new

  # the zero case...
  if self == 0
    base34_str << UserFriendlyId::BASE34_DIGITS[0]
    return base34_str
  end

  # get sign...
  sign = self/(self.abs)

  # make a working copy of self...
  work = self.abs

  # we build the base34 number from right to left...
  place = 0
  while work > 0 do
    # grab the portion that is representable in our 'place' before we have to increment up to the next 'place'
    remainder =  work % (34**(place+1))
    # build the base34 number from right to left (i.e, tack on at the front)...
    base34_str.insert(0, UserFriendlyId::BASE34_DIGITS[remainder/(34**place)])
    # remove the portion we just represented...
    work = work - remainder
    # keep going...
    place += 1
  end

  # append a negative sign if negative...
  if sign < 0
    base34_str.insert(0,'-')
  end

  return base34_str
end