anchor.diff:      abstract member DefinePush : unit -> Op<'x, 'x S>
   
   type private PrimitiveColumnGenerator(builder, column, primitive : Primitive) =
  -    inherit EntityReaderColumnGenerator(builder, column)
  +    inherit EntityReaderColumnGenerator(builder)
       let output = column.Blueprint.Value.Output
       let mutable colValue = null
       let mutable colInfo = null
  
positive.code: 
  and private ManyColumnGenerator
      ( builder
      , column
      , element : ElementBlueprint
      , elementId : Column
      , conversion : ConversionMethod
      ) =
      inherit EntityReaderColumnGenerator(builder, column)
      let elemTy = element.Output
      let staticTemplate = typedefof<_ StaticEntityReaderTemplate>.MakeGenericType(elemTy)
      let entTemplate = typedefof<_ EntityReaderTemplate>.MakeGenericType(elemTy)
  
negative.code:         | One { Shape = Composite c } ->
              CompositeColumnGenerator(builder, column, c) :> EntityReaderColumnGenerator
          | Many (element, conversion) ->
              ManyColumnGenerator(builder, Some column, element, conversion) :> EntityReaderColumnGenerator
  
      static member ImplementReader(builder : TypeBuilder, ty : Type, primitive : Primitive, readerBuilder) =
          let info = builder.DefineField("_i", typeof<ColumnInfo>, FieldAttributes.Private)
          let value = builder.DefineField("_v", ty, FieldAttributes.Private)
  