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0 pointsquonn5y ago0 comments

It helps a lot with refactoring and many other things even early in the project.

For example I‘m using TypeScript with a GraphQL code generator. Now let‘s assume I add a new value to a GraphQL enum. I run codegen, then fix everything until the compiler is happy. Afterwards, all places where this enum was ever touched will take it into account correctly, including mappings, translations, all switch statements, conditions, lists where some of the other values are mentioned and so on.

This is something that‘s not possible in a dynamic language and it‘s not even possible in Java, really.

I rely on this daily.

0 comments

archarios5y ago

You could do the same process if you used dynamic typing and good test coverage. Just make your change and keep fixing tests until everything is green.

wtetzner5y ago

But how could you have written tests against that new enum value if it didn't exist before? You would need to know in advance which places needed to be tested for it.

Ar-Curunir5y ago

Then you essentially are implementing a type checker in your tests, but worse

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