Implement deleteat! and append!

[nalimilan]

Fixes #22.

[bkamins]

Looks good. append! is probably even more safe than what we have in _vcat below 😄.

[nalimilan]

This doesn't support append! from a generic iterable, but I think fallback methods should be defined in Base since it already contains methods which use resize! and setindex! or push!, which are perfectly generic. It sounds silly to redefine these in all packages.

[bkamins]

The problem is that in Julia 1.0 this is not present so if we aim at long-term support maybe we should conditionally define them (and now they would always be defined in the package)?

[nalimilan]

This would ensure entries are set to #undef in case conversion fails for some values:

Suggested change

	resize!(pv.refs, l+n)
	resize!(pv, l+n)

That's not what happens for Arrays of isbits types, but maybe that's worth it here given that PooledArray is mostly useful for non-isbits types? Otherwise, leaving refs undefined could trigger crashes.

[bkamins]

I understand that you are afraid that later copyto! will not set the proper values there?

[nalimilan]

Yes, if conversion fails it will stop in the middle AFAIK.

[nalimilan]

The problem is that in Julia 1.0 this is not present so if we aim at long-term support maybe we should conditionally define them (and now they would always be defined in the package)?

Yeah, but honestly I don't really care. :-)

At least let's get this included in Base first so that we know what VERSION check to use: JuliaLang/julia#32065.

[bkamins]

I think that we should care :), I answer SO a lot, and people report there often that they are stuck with 1.0 when I give them some solutions that use 1.1 features.

[bkamins]

Also insert!, splice! and prepend! should be added to be consistent with Vector API.

[nalimilan]

Bump.

[bkamins]

I think it is good to merge. Adding other Vector operations that are still undefined can be done in a separate PR (changes in JuliaData/WeakRefStrings.jl#63 gives a list what should be implemented)

[bkamins]

bump (as this package is getting used more by the community and the problem is repeatedly reported)

[nalimilan]

@shashi @JeffBezanson OK to merge?

[quinnj]

Looks good. I forgot I have access rights here.

[bkamins]

@quinnj can you also please tag a release then? Thank you.