Excise MersenneTwister

[PallHaraldsson]

It seems like we can and maybe should do it. Likely most aren't using, rather the new default RNG automatically, for some years now.

I'm not sure it takes (much) space in the sysimage (and/or Random) for little gain. It could always be added back, or lazy loaded.

[PallHaraldsson]

I do see additionally (and is this DSFMT only used by MersenneTwister, and also taking up too much space/time?):

include("DSFMT.jl")

using .DSFMT
using Base.GMP.MPZ
using Base.GMP: Limb

I didn't look up what GMP is used for, but it seems not to to allow generating random rand(BigInt) didn't work for me, so for MT? I actually want to excise BigInt/GMP also but not all in one go... and also BigFloat, not now but earlier. ArbNumerics.jl is better, all should be using that. Is rand(BigFloat) terribly important to most people?

[vchuravy]

I think the right pathway is to excise random #51432

[andrewjradcliffe]

MT should be eliminated for more reasons than just sysimage size.

[PallHaraldsson]

I think the right pathway is to excise random #51432

Isn't that about making Random an (upgradable? is that needed?) stdlib? Anyway it would keep MT there?

MT should be eliminated for more reasons than just sysimage size.

Given that, could we "lie" to users (to sort of not break code) with (but document in NEWS?):

const MersenneTwister = Xoshiro # and deprecate it right away, I think it's not yet done.

I mean we could, and most users wouldn't care..., most don't user it currently any more, would some opt into it for a good reason or out of ignorance?

If someone really needs MersenneTwister (exact stream on those random numbers) it could be added back with a package MersenneTwister.jl.