> That doesn’t quite seem to do what you want, Mauro:

Yes, you're right, sorry for the noise!

> julia> arr_of_arr = Vector{Int}[[1],[2,3],[4,5]]
> 3-element Array{Array{Int64,1},1}:
>  [1]
>  [2,3]
>  [4,5]
>
> julia> vcat_nosplat(y) = eltype(y[1])[el[1] for el in y]
> vcat_nosplat (generic function with 1 method)
>
> julia> vcat_nosplat(arr_of_arr)
> 3-element Array{Int64,1}:
>  1
>  2
>  4
>
> It’s quite trivial to achieve the desired result with only a few lines of
> code, though:
>
> julia> function vcat_nosplat2(y)
>        result = Array(eltype(y[1]), 0)
>        sizehint!(result, sum(map(length, y))) #skip if iterating is more 
> expensive than reallcoation
>
>        for a in y
>            for x in a
>                push!(result, x)
>            end
>        end
>
>        result
>        end
> vcat_nosplat2 (generic function with 1 method)
>
> julia> vcat_nosplat2(arr_of_arr)
> 5-element Array{Int64,1}:
>  1
>  2
>  3
>  4
>  5
>
> // T
>
> On Sunday, November 22, 2015 at 9:12:55 PM UTC+1, Mauro wrote:
>
> In ODE.jl, I've used
>>
>> vcat_nosplat(y) = eltype(y[1])[el[1] for el in y] # Does vcat(y...)
>> without the splatting
>>
>> I think the eltype might not be needed.  There may be better ways though.
>>
>> On Sun, 2015-11-22 at 14:04, Cedric St-Jean <cedric...@gmail.com
>> <javascript:>> wrote:
>> > I have a big vector of vectors. Is there any way to vcat/hcat them
>> without
>> > splatting?
>> >
>> > arr_of_arr = Vector[[1],[2,3],[4,5]]
>> > vcat(arr_of_arr...)
>> >
>> > I'm asking because splatting big arrays is a performance issue (and IIRC
>> it
>> > blows the stack at some point).
>>
>

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