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
- HEAD
- UINT8
Public Class Methods
[](term)
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# 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)
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# 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)
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# 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))
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# 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