Write a cool pretty printer for an `Encoding`

[well-typed]

Write a cool pretty printer for an `Encoding`

[dcoutts]

We can do this by decoding the Tokens to a Term and pretty printing the Term in CBOR syntax.

The testsuite already has a function diagnosticNotation :: Term -> String that produces the CBOR syntax (though it's for a type from the reference impl so some changes would be needed).

So yes, this should be straightforward and indeed useful. Perhaps we should make that the show instance for Encoding.

[arianvp]

Something like: http://cbor.me/ ?

Which prints out these kind of useful messages:

a1       # map(1)
   61    # text(1)
      61 # "a"
   83    # array(3)
      01 # unsigned(1)
      03 # unsigned(3)
      04 # unsigned(4)

Or do you mean showing the json-like representation of an encoding?

{"a": [1, 3, 4]}

[thoughtpolice]

Why not both! We could have a .Pretty module with multiple functions! :)

[dcoutts]

I meant the latter form, which is informally specified in the CBOR spec, and which we already generate in the tests to compare to the reference test vectors.

[axman6]

I started implementing this, but got stuck when trying to use FlatTerm instead of Encoding directly. I'll give it another go this week if I find time. (Edit: Removed the useless code that was here to reduce noise)

[axman6]

Obviously this is missing the hex representation, which should be easier to produce with Encoding.

[thoughtpolice]

Closed by c1cafbe. We'll do future work in other tickets if necessary.