Integer power of large Integer returning very wrong results

I am with Julia 1.9 on a fresh session (windows). (Maybe it happens on previous version already)
Is it normal to get stuff like

julia> 5^2000

julia> 2^200

With floating power 5^2000., it is Inf.

That is just integer overflow. Normal julia Ints aren’t BigInts.

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Why not Inf everywhere?

Inf is a floating point thing. One could use checked integer arithmetic that would throw an exception on overflow like GitHub - JeffreySarnoff/SaferIntegers.jl: These integer types use checked arithmetic, otherwise they are as system types.. But they are slow, so julia doesn’t do that by default

For the second time this week I can dig out this classic thread:


And I’ll plug OverflowContexts.jl (GitHub - BioTurboNick/OverflowContexts.jl: Fine control of integer overflow checking.) if you’d like control over it.

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Why not Inf everywhere?

Because Inf is NOT a part of Int64

Thanks for all your answers, I missed these link in my pre-question search.
Plus I missed Julia docs on that.

I missed the “overflow” keyword.