class Erlang::ETF::SmallBig

| 1 | 1 | 1 | n | | — | — | —- | ————— | | 110 | n | Sign | d(0) … d(n-1) |

Bignums are stored in unary form with a `Sign` byte that is 0 if the binum is positive and 1 if is negative. The digits are stored with the LSB byte stored first.

To calculate the integer the following formula can be used:

“` B = 256 (d0*B^0 + d1*B^1 + d2*B^2 + … d(N-1)*B^(n-1)) “`

(see [`SMALL_BIG_EXT`])

[`SMALL_BIG_EXT`]: erlang.org/doc/apps/erts/erl_ext_dist.html#SMALL_BIG_EXT

Constants

UINT8

Public Class Methods

[](term) click to toggle source
# File lib/erlang/etf/small_big.rb, line 31
def [](term)
  return term if term.kind_of?(Erlang::ETF::Term)
  term = Erlang.from(term)
  return new(term)
end
erlang_load(buffer) click to toggle source
# File lib/erlang/etf/small_big.rb, line 37
def erlang_load(buffer)
  n, sign, = buffer.read(2).unpack(HEAD)
  integer = Erlang::Binary.decode_unsigned(buffer.read(n), :little)
  integer = -integer if sign == 1
  return new(integer)
end
new(term) click to toggle source
# File lib/erlang/etf/small_big.rb, line 45
def initialize(term)
  raise ArgumentError, "term must be of type Integer" if not Erlang.is_integer(term)
  @term = term
end

Public Instance Methods

erlang_dump(buffer = ::String.new.force_encoding(BINARY_ENCODING)) click to toggle source
# File lib/erlang/etf/small_big.rb, line 50
def erlang_dump(buffer = ::String.new.force_encoding(BINARY_ENCODING))
  buffer << SMALL_BIG_EXT
  buffer << [Erlang::ETF.intlog2div8(@term), (@term < 0) ? 1 : 0].pack(HEAD)
  buffer << Erlang::Binary.encode_unsigned(@term.abs, :little)
  return buffer
end