Element type inference isn’t done by the compiler, there’s a separate mechanism for Array literals, and in your case it’s making a broader type than you’d like. You also don’t want the compiler doing element type inference the way it does variable type inference because it would infer the Union of the two types that lmiq mentioned, which you also don’t want. The discrepancy is because the compiler is incentivized to narrow things down as much as possible, while a mutable array is incentivized to permit more types by typejoining or promotion. Manual inference is the way to go here because no automatic inference can satisfy every use case; the type you did get or the narrowest Union could be satisfactory results in other contexts, and the algorithm cannot know which.
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