Nascent Idea: allow `.0`, `.1`, etc on arrays

language design
11

x.N is too restricting lexically, you can't put an arbitrary constant there (which would be useful with variadics).

Adding hacks to x[EXPR] to detect x[CONST_EXPR] and treat it differently (avoid overloading, switch to field access semantics) doesn't feel like a good solution to me (this is also a breaking change technically).

Perhaps a separate non-overloadable operator x.[CONST_EXPR] would be more appropriate for compile-time indexing, but the motivation is probably not large enough until variadics arrive.

The separate operator could be used with arbitrary structs as well

struct S { field: u8 }

let s = S { field: 10 };
let z = s.[0]; // z = 10

except that use from other crates need to be prohibited by default to allow arbitrary field reordering without causing compatibility issues.

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