in src/arraytypes/fixedsizelist.jl [124:146]
function arrowvector(
::FixedSizeListKind{N,T},
x,
i,
nl,
fi,
de,
ded,
meta;
kw...,
) where {N,T}
len = length(x)
validity = ValidityBitmap(x)
flat = ToFixedSizeList(x)
if eltype(flat) == UInt8
data = flat
S = origtype(flat)
else
data = arrowvector(flat, i, nl + 1, fi, de, ded, nothing; kw...)
S = withmissing(eltype(x), NTuple{N,eltype(data)})
end
return FixedSizeList{S,typeof(data)}(UInt8[], validity, data, len, meta)
end