Julia: move `Future.copy!` to Base

[chethega]

help?> copy!
search: copy! copyto! circcopy! unsafe_copyto! copy copysign deepcopy

  copy!(dst, src)

  In-place copy of src into dst. After the call to copy!, dst must be left
  equal to src, otherwise an error is thrown; this function appropriately
  resizes dst if necessary. See also copyto!.

Well, sounds convenient for a preallocated dst::Vector{T}, src::AbstractVector{T}. Alas,

julia> methods(copy!)
# 4 methods for generic function "copy!":
[1] copy!(dst::Random.MersenneTwister, src::Random.MersenneTwister) in Random at /build/julia/src/julia/usr/share/julia/stdlib/v1.0/Random/src/RNGs.jl:142
[2] copy!(dst::Random.DSFMT.DSFMT_state, src::Random.DSFMT.DSFMT_state) in Random.DSFMT at /build/julia/src/julia/usr/share/julia/stdlib/v1.0/Random/src/DSFMT.jl:37
[3] copy!(a::LibGit2.GitCredential, b::LibGit2.GitCredential) in LibGit2 at /build/julia/src/julia/usr/share/julia/stdlib/v1.0/LibGit2/src/gitcredential.jl:83
[4] copy!(dest::BitSet, src::BitSet) in Base at bitset.jl:58

I guess the docs went out of sync and copy! was deprecated for ( length(dst)==length(src) || resize!(dst, length(src)) ); copyto!(dst, src) at some point? I'm not sure whether the documented functionality really needs to exist, but either way, reality and doc should match.

For the next release, if copy! does not come back, can we rename the other copy! methods to something less prominent then? The BitSet! copy! probably needs to stay for now, since it is in base and would be breaking?

[fredrikekre]

We just need to move Future.copy! to Base.

[chethega]

Oops, sorry I missed that. So this is according to plan and the docs just updated faster than the actual stuff?

Close issue as PEBCAK, or move copy! now or change docs for the meantime?

[fredrikekre]

I mean... the docs are not wrong, they don't say this works for vectors. Its just not yet implemented for vectors.

[JeffBezanson]

I think we can move Future.copy! to Base right away. It could have been done for 1.0.

[rfourquet]

It could have been done for 1.0

I thought so, but 1.0 was out before I had time to ask whether it should go into 1.0 or 1.1 ;-)