# Error during initialization
**URL:** https://discourse.julialang.org/t/error-during-initialization/9907
**Category:** New to Julia
**Tags:** question
**Created:** [March 22, 2018, 9:37pm UTC](https://discourse.julialang.org/t/error-during-initialization/9907 "2018-03-22T21:37:53Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@leoll2](https://discourse.julialang.org/u/leoll2)
#### Post date: [March 22, 2018, 9:37pm UTC](https://discourse.julialang.org/t/error-during-initialization/9907/1 "2018-03-22T21:37:53Z")
I hate to ask these kind of questions, but I can’t understand why this code doesn’t work. Apparently the problem is a stackoverflow error, which seems to be generated in the build\_bar() function, when assigning. The new BarType is initially a vector of undef values, then I initialize it.
As far as I know, this should be legal, since I also tested a more complex code (with parametric types) which does likewise but works fine.
Any tip? Thanks!
> using OffsetArrays
>
> struct FooType \<: AbstractArray{Float64,1}
> data::OffsetArray{Float64,1}
> dim::Int64
> end
>
> FooType(n::Int) = FooType(OffsetArray(Float64, 1:n), n)
> Base.size(s::FooType) = (s.dim,)
> Base.IndexStyle(::Type{\<:FooType}) = IndexLinear()
> Base.similar(s::FooType, ::Type, d::Dims) = FooType(d[1])
> Base.getindex(s::FooType, i::Int) = s.data[i]
> Base.setindex!(s::FooType, v, i::Int) = (s.data[i] = v)
> Base.show(io::IO, s::FooType) = print(io, s)
> Base.indices(s::FooType) = indices(s.data)
> Base.:(==)(a::FooType, b::FooType) = a.data == b.data
> Base.isless(a::FooType, b::FooType) = a[1]\
> struct BarType \<: AbstractArray{FooType,1}
> data::Array{FooType,1}
> dim::Int64
> end
>
> function build\_bar(m::Int, n::Int)
> bar = BarType(Array{FooType,1}(m), m)
> for i in 1:m
> bar.data[i] = FooType(n)
> end
> bar
> end
>
> BarType(m::Int, n::Int) = build\_bar(m,n)
> Base.size(b::BarType) = (b.dim,)
> Base.IndexStyle(::Type{\<:BarType}) = IndexLinear()
> Base.similar(b::BarType, ::Type, d::Dims) = BarType(d[1])
> Base.getindex(b::BarType, i::Int) = b.data[i]
> Base.setindex!(b::BarType, val, i::Int) = (b.data[i] = val)
> Base.show(io::IO, b::BarType) = print(io, b.dim)
> Base.indices(b::BarType) = indices(b.data)
>
> b = BarType(3,2)
---
### Author:  [@rdeits](https://discourse.julialang.org/u/rdeits)
#### Post date: [March 22, 2018, 10:04pm UTC](https://discourse.julialang.org/t/error-during-initialization/9907/2 "2018-03-22T22:04:18Z")
> [@leoll2](#):
>
> Base.show(io::IO, s::FooType) = print(io, s)
Your `show` method calls `print` which calls `show` which calls `print` which calls `show` etc, which is how you get a stack overflow error. This only happens at the end of your code when Julia tries to display your `BarType` and its contained `FooType`s. The easiest thing to do is to just delete that `show` method since it’s doing nothing useful for you.
If you want a custom `show()` make sure that what you `print()` isn’t just the same thing that was passed to `show()`. For example, this works fine:
```julia
julia> Base.show(io::IO, s::FooType) = print(io, "FooType with data: $(s.data)")
julia> b = BarType(3,2)
3-element BarType:
FooType with data: [NaN, 0.0]
FooType with data: [2.42531e-314, 2.29997e-314]
FooType with data: [2.97131e-320, 0.0]
```