/hex

A simple hex viewer for Elm Bytes values

Primary LanguageElmBSD 3-Clause "New" or "Revised" LicenseBSD-3-Clause

Hex.Convert

Hex.Convert is a small package for working with elm/bytes. It exposes three functions.

  • toString : Bytes -> String
  • toBytes : String -> Maybe Bytes
  • blocks : Int -> String -> List String

The toString function converts a Bytes value into its hexadecimal representation, assuming this exists. For example, something like "6A45F2". The toBytes function converts a string like "6A45F2" to a value of type Maybe Bytes. Such a function call can fail, e.g., on the input "6A45F!". The blocks function is useful for grouping a long string into shorter substrings of equal length.

Examples

Hex.Convert.toBytes "FF66"  
    |> Maybe.map Hex.Convert.toString 
--> Just "FF66"`

$ elm repl
> import Hex.Convert
> import Bytes.Encode as Encode exposing(encode)

> encode (Encode.string "Hello") 
    |> Hex.Convert.toString
"48656C6C6F" : String

> Hex.Convert.toBytes "FF66" 
    |> Maybe.map Hex.Convert.toString
Just "FF66" : Maybe String

> Hex.Convert.toBytes "FF66!!" 
    |> Maybe.map Hex.Convert.toString
Nothing : Maybe String

> "abcdefghijklmnopqrstuvwx1234" 
    |> Hex.Convert.blocks 4
["abcd","efgh","ijkl","mnop","qrst","uvwx","1234"]


## Notes

The function `Hex.Convert.toBytes` is case-insensitive. Thus

    Hex.Convert.toBytes "ff66" 
        |> Maybe.map Hex.Convert.toString
    --> Just "FF66"

If you prefer lower-case output from `Hex.Convert.from`,
you can do as in this example:

    Hex.Convert.toBytes "ff66" 
        |> Maybe.map Hex.Convert.toString 
        |> Maybe.map String.toLower
    --> Just "ff66" : Maybe String