Module: SpaceCadetUuidId

Included in:
SpaceCadetUuid
Defined in:
lib/space_cadet_uuid_id.rb

Instance Method Summary collapse

Instance Method Details

#high_order_bits_from_hex_string(hex_string, bit_count) ⇒ Object 



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# File 'lib/space_cadet_uuid_id.rb', line 13

def high_order_bits_from_hex_string hex_string, bit_count
  total_bit_count = hex_string.length << 2
  num = num_from_hex_string hex_string
  num >> (total_bit_count - bit_count)
end

#id_from_uuid(uuid, id_bit_count) ⇒ Object 



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# File 'lib/space_cadet_uuid_id.rb', line 24

def id_from_uuid uuid, id_bit_count
  hex_string = uuid[24..-1]
  low_order_bits_from_hex_string hex_string, id_bit_count
end

#low_order_bits_from_hex_string(hex_string, bit_count) ⇒ Object 



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# File 'lib/space_cadet_uuid_id.rb', line 19

def low_order_bits_from_hex_string hex_string, bit_count
  num = num_from_hex_string hex_string
  num & ((1 << bit_count) - 1)
end

#num_from_hex_string(hex_string) ⇒ Object 



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# File 'lib/space_cadet_uuid_id.rb', line 9

def num_from_hex_string hex_string
  hex_string.bytes.reduce(0, &->(num,b){num <<= 4;num += HEX_DIGIT[b]})
end