Some questions on useability

[GregPlowman]

Well, firstly thanks for providing OffsetArrays.

I want to make it simpler/cleaner to specify OffsetArrays backed by standard arrays. And also use analogous syntax to standard Arrays for creating and typing OffsetArrays.

An example might be best:

type MyType
    x::OffsetStdVector{Int} 
    y::OffsetStdArray{Float64,2}
end

a = OffsetVector{Int}(0:5) 
b = OffsetArray{Float64}(0:12, -1:1) 
c = MyType(a, b)

a = zeros(Int, 0:5)    # [3]
b = zeros(Float64, 0:12, -1:1)    #[3]
c = MyType(a, b)

This can be achieved currently with something like:

using OffsetArrays
import OffsetArrays.OffsetVector

typealias OffsetStdVector{T}  OffsetArray{T,1,Array{T,1}}
typealias OffsetStdArray{T,N} OffsetArray{T,N,Array{T,N}}

(::Type{OffsetVector{T}}){T}(inds::UnitRange{Int}) = OffsetArray{T}(inds)
(::Type{OffsetArray{T}}){T}(inds::UnitRange{Int}...) = OffsetArray{T}(inds)

Base.zeros{N}(T::Type, inds::Base.Indices{N}) = fill!(OffsetArray{T}(inds), zero(T))
Base.zeros(T::Type, inds::UnitRange{Int}...) = zeros(T, inds)

Ideally OffsetArray could be renamed to say OffsetGenArray, so that standard array-backed type could be just OffsetArray

In any case,

1. Could OffsetVector be exported?
2. Is there any problem with defining methods so that OffsetArray{T}(inds) can construct (similar to recommended way to construct standard arrays)?
3. Why is zero deprecated? using syntax as above seems quite natural to me.

[timholy]

Could OffsetVector be exported?

I don't see why not. Care to submit a PR?

Is there any problem with defining methods so that OffsetArray{T}(inds) can construct (similar to recommended way to construct standard arrays)?

Perhaps, see below.

Why is zero deprecated? using syntax as above seems quite natural to me.

See #12 (comment).

The fundamental problem is to distinguish a range that specifies indices from an AbstractArray that you'd like to wrap. Is OffsetArray(a, b) wrapping a, or does a describe the indices?

[timholy]

#26 will add some constructors that we were missing, and OffsetVector was added some time ago.

The only part of this we can't do is the zeros/ones bit. However, thanks to JuliaLang/julia#19635, by Julia 1.0 we should be able to do this.