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- Subject: Re: Definion of 'for' statement in the manual
- From: Dirk Laurie <dirk.laurie@...>
- Date: Sat, 26 Sep 2015 21:02:16 +0200
2015-09-26 20:32 GMT+02:00 Roberto Ierusalimschy <email@example.com>:
>> >> Why does Lua 5.3's reference does "var = var - step" instead of simply
>> >> moving the "var = var + step" after "block" (as in Lua 5.2)?
>> > This is how it is implemented, and both ways can give different results.
>> > (That it is why we do not like to specify things with code, it gives too
>> > much details that should be left open.)
>> How could both ways give different results?
> Floating point operations. See the next example:
> > for i = -2^53, -2^53 + 2 do print(string.format("%.0f", i)) end
> (Note that the given initial value, -2^53, is -9007199254740992.)
On my machine Lua 5.1, 5.2, 5.3 all give that, so where is the