Two arrays of the same size and element type but with different index
boundaries seem to be distinct types for the purpose of (polymorphic) proc
definitions, so this compiles:
proc p(a: array[10, int]) = discard
proc p(a: array[-1 .. 8, int]) = discard
but they seem to be treated as identical when attempt to call this proc is
made, so this:
var a: array[10, int]
p(a)
fails to compile with the following error message:
test.nim(6, 2) Error: ambiguous call; both test.p(a: array[0..9,
int])[declared in test.nim(1, 5)] and test.p(a: array[-1..8, int])[declared in
test.nim(2, 5)] match for: (array[0..9, int])
Nim compiler version:
> nim -v
Nim Compiler Version 0.17.2 (2017-09-07) [Windows: amd64]
Copyright (c) 2006-2017 by Andreas Rumpf
git hash: 811fbdafd958443ddac98ad58c77245860b38620
active boot switches: -d:release
I understand that this example may seem rather synthetic (though I actually run
into this while testing an idea of providing two different indexing schemes for
C-array used in some external C DLL call), but the situation when you can
declare something that you cannot later call looks rather strange and
inconsistent.
