Created
November 2, 2010 17:35
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Converts a bitstring into a number
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-spec(bitstring_to_number/1::(BitString::bitstring()) -> number()). | |
bitstring_to_number(BitString) -> | |
bitstring_to_number(BitString, bit_size(BitString), 0). | |
bitstring_to_number(_BitString, 0, Acc) -> Acc; | |
bitstring_to_number(BitString, CurrBitNum, Acc) -> | |
BitsToSkip = bit_size(BitString) - CurrBitNum, | |
<<_:BitsToSkip/bitstring, CurrentBit:1/bitstring, _/bitstring>> = BitString, | |
Addition = case CurrentBit of | |
<<1:1>> -> 1 bsl (CurrBitNum - 1); | |
_ -> 0 | |
end, | |
bitstring_to_number(BitString, CurrBitNum - 1, Acc + Addition). |
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