lensify.org

Lensification

Goals

• Get used to lenses myself.
• Clean up the IR to the point where a lot of mechanical code gets replaced with smaller idiomatic lens code.
• Have a clean basis for a query/filtering language.
• Build the query/filtering language as a parser that builds lenses.

Clean up IR

Layout

• This is going to be some work!
• What operations do I want to do? Let them guide my work.

Layout Operations

• Calculate Padding
• Fetch data from stream!
  • This is the big one.
  • Make a lens for each LayoutMember, and have it let me directly read/write Primitive wrappers?. Type: Lens ByteStream PrimitiveValue
    • With some code that reads/writes the value back into the stream. It wraps the lens. valueLens
    • Well, we don’t need just ONE Something that generates the lens we want would do the trick here.
      • A proper meta system.
      • Representations of the meta system?
        • Look at what I want to build:
          • Read / write data
          • Query/calc offsets
    • Synthetic values are Folds over lenses.
      • Regular values are pass-through lenses from ParsedRep to layout. ParsedRep synthetics are composed of the layout lenses.
    • For the buffer, a Prism for the bytestream is what we need. With an implicit Nothing value for seqno errors.

ParsedRep

• Useful for rewriting the JSON later.
• Based off of Layout.

Analysis

Can I generate lens definitions (or have a generator in haskell!) that makes lenses for me, that I can then use against the raw capture data in iHaskell?

• That seems the most natural.