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On Thu, Jul 14, 2016 at 6:19 PM, Sergey Rozhenko <sergroj@gmail.com> wrote:
> On Пт 15.07.16 2:57, Sean Conner wrote:
>>
>>    Oh, so to clarify (kind of making the bigint library up):
>>
>>         bi = require "bigint"
>>
>>         x = bi.make(2^128) -- syntax issues but I want something
>>         y = bi.make(2^128) -- really really large
>>
>>         t = {}
>>         t[x] = "booya!"
>>         print(t[y])
>>         booya!
>
>
> In this case __key would help at all. With or without it you'd have to keep
> a cache of these values, because it's needed to make __key return the same
> object. So, it's easier to make bi.make return the same object for both
> calls instead.

That's not true at all. bi.__key could return a Lua "number"-type
value when the value is representable without loss of precision or a
string otherwise. This would provide for the nice property of
"t[bi.make(100)] == t[100]" in addition to the "t[x] == t[y]" desired
in the example.

/s/ Adam