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0 pointseitland5y ago0 comments

Have my upvote for the serious answer. Let's just say we have different opinions.

Here's my attempt to create something similar from my perspective:

- Being able to know to at any point what a variable can contain is very liberating. (Ok, you can define a list of Object that behaves just like a list in JS: "fully dynamic, not type restricted", but thankfully for people like me that is not common in Java anymore.)

- Knowing that the compiler has my back allows me to work faster.

- My preferred languages (Java, C#, TypeScript) together with version control allows me to refactor fearlessly.

0 comments

vorpalhex5y ago

It's a tradeoff. Dynamic isn't "better" than typesafety, but it's generally easier to comprehend and reason about. Just yesterday, I was working on a C# script and encountered the following problem:

+ An engineer had written a script with a Dictionary of type <Transform, Material>. If you've touched Unity, you immediately caught the flaw: Transform's aren't unique enough keys and it's really easy to end up trying to add Duplicate keys, even though you really mean different objects.

+ So, since we don't care about uniqueness, shift from a Dictionary to a List. Except we have a problem, because we need to keep that Key->Value relation so we know what transforms get what materials. Well, we have a solution to that, it's yet-another-type called a KeyValuePair.

+ Well we're now nesting a generic KeyValuePair that needs type information inside of a list that is holding <KeyValuePair> objects, which also changes how we iterate through that list and add items to it.

+ In a language like JS, everything I just said doesn't matter at all because instead of using a Dictionary (Map in JS), we would of just said "Use a Set instead". Done.

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