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by wellpast 3155 days ago
How would it infer:

   isOld(parseJson(json))
When parseJson may or may not produce an entity with the "age" property?
1 comments

Sorry, I wasn't clear. My point was that you don't have to declare the type of `thing` up front in that example. It would be able to infer that it's a record with an `age` field from the function's definition.

In your example, `parseJson` would have to return a record with an age field, otherwise the compiler would complain. Personally, I think that represents a reasonable tradeoff in ease of use for safety.