Type Synonyms?

[markandrus]

Hi,

I am trying to use dhall-bash for some more strongly-typed configuration I typically consume from Bash scripts. To this end, I want to introduce type synonyms for my configuration to distinguish various types of strings. I'm not sure how to make this work, though. Can you point me in the right direction? Here is my test script, test.dhall:

let MyText : Type = Text
in "Hello, World!" : MyText

And here is the output I receive:

$ dhall-to-bash < test.dhall


MyText : Type

Error: Expression doesn't match annotation

"Hello, World!" : MyText

(stdin):2:4

Thanks,
Mark

[Gabriella439]

This is related to the following two issues:

• Type annotation cannot refer bindings in scope dhall-haskell#10
• Type synonyms for Haskell defined types dhall-haskell#92

To summarize, those two issues, the current implementation only lets you share types via the import system, like this:

$ cat ./MyText
Text
$ cat example
"Hello, world!" : ./MyText

[markandrus]

Ah, thanks very much @Gabriel439. I do wish there was some syntactic sugar on top of the import system for types that would allow me to land the MyText type in the same file, rather than in a separate file, but perhaps that should be discussed elsewhere. I will close this ticket now.

Thank you,
Mark

[Gabriella439]

You're welcome!