var list = const [3];list[0] = 9;should throw error in compile time

[LuoJimmy]

var list = const [3];
list[0] = 9; // error in runtime, but this can analyze in compile time.

var list2 = List.unmodifiable([3]);
list2[0] = 99; // this should error in runtime not in compile time.

[lrhn]

This is a restriction that the type system doesn't capture. There is no way to look at the variable list or list2 of type List<int> and see that it's unmodifiable.

The analyzer can likely detect that the only possible values of that variable at that point are unmodifiable lists (and have the ability to know about unmodifiable lists to begin with, something the language specification doesn't even know about), and could possibly give a warning here.

So, not possible as a compile-time error. Might be possible to get a warning, but then it's not a language issue.

[srawlins]

#48551 is a duplicate request. It is newer, but has more discussion, so I'm closing this in favor of that.