Hi,All I have the following structures: data Life_Type = Life_Type with id : Optional Text coverage : [Coverage_Type] data Coverage_Type = Coverage_Type with productCode : Optional Text When I try to do: let coverageLayerList = life.coverage filteredByProductCode = filter (\r → r.prod…

@cocreature Thank you very much! This really helped me understand the problem and learn from it

Could you share a bit more of your code? I can’t spot anything in the snippet you posted but I suspect the way you use filteredByProductCode may be the problem. It would be great if you could embed your code in a code block to make sure indentation is preserved and it’s easier to read. Just wrap it…

@cocreature Thank you . Here is the relevant code snippet [image]

The issue is in the type of coverageType. First, remember that all branches in a case statement must have the same type. Looking at the first branch, you return None. So coverageType must be of type Optional a for some type a. That’s the Optional a0 you see in the error. Looking at the second bran…

Couldn't match type error

App Development

Stephen September 12, 2022, 3:46pm 6

Please use ``` around both code samples and errors, and avoid posting screenshots of code or errors, as explained here.

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Couldn't match type error

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