How to convert String to BinaryLiterals

Question

Is there anyway to convert String to BinaryLiterals type?

For example "11001100" to 0b11001100

BinaryLiterals is not a type but an extension that lets you type in numbers in binary which then are interpreted as any other number (i.e. `fromInteger`). If you simply want to parse binary then you could map `digitToInt` and `zipWith (*) powersOfTwo`. — Thomas M. DuBuisson, Jan 02 '18 at 18:27

Mark Seemann · Accepted Answer · 2018-01-02T19:00:55.737

Using readBin from https://stackoverflow.com/a/5922212/126014, you can parse a binary string representation of a number into an Maybe Integral of your choice, e.g.:

*Q48065932> readBin "11001100"
Just 204

11001100 is just the binary representation of the (decimal) integer 204. Using BinaryLiterals, you can write that number using binary representation:

*Q48065932> :set -XBinaryLiterals
*Q48065932> Just 0b11001100
Just 204

If you want the integer to be a particular type (say: Word8), you can do that for both expressions:

*Q48065932 Data.Word> readBin "11001100" :: Maybe Word8
Just 204
*Q48065932 Data.Word> Just 0b11001100 :: Maybe Word8
Just 204

You can convince yourself that these two expressions have the same value by comparing them:

*Q48065932 Data.Word> readBin "11001100" == Just 0b11001100
True

You can also write the number 204 using hexadecimal notation, like this:

*Q48065932 Data.Word> Just 0xCC
Just 204

That's still equal to 11001100:

*Q48065932 Data.Word> Just 0xCC == readBin "11001100"
True
*Q48065932 Data.Word> Just 0xCC == Just 204
True

All of these expressions are equal to each other because they're the same number (204); they're just different ways to write the same number. The data type used to store that number in memory (Int, Word8, etc.) is independent of how you write the literal numbers.

How to convert String to BinaryLiterals

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