Reexporting modules across DARs

Questions
,
1

I wanted to a convenience module where I export some other modules. For example assume I have something like this:

module Examples.Example (
    answer
  , Fruit (..)
) where

answer : Int
answer = 42

data Fruit = Apple | Banana | Cherry

Then I create the convenience module:

module Examples.All (
  module Examples.Example
) where

import Examples.Example

This works in the project where I define these modules. Meaning if I do import Examples.All the things defined in Example are available.

This does not seem to work across DARs though. So assume I added the examples.dar as a data-dependency to the examples-test project. Now, even I have the import for the convenience module the things defined in Example are not available.

Is this by design? Did I do something wrong or missed something?

2 Likes
2

I’m not sure about the “by design” part, but it’s definitely known behaviour/limitation for data-dependencies: these are dependencies on Daml-LF files, rather than Daml source files, and Daml-LF does not have a notion of module declaration: a Daml-LF module is just a bunch of code. No hiding, no reexport.

1 Like
3

So out of curiosity does this work with the other type of dependency? What is it, just depdendencies: in the daml.yaml file, instead of data-dependencies:?

1 Like
4

It works with dependencies but not data-dependencies. I’d still recommend against relying on it since it can lead to confusion since over the JSON and Ledger API you’ll be working with the non-reexported module names.

1 Like