Hi Julia Users,
So I was looking at ConjugatePriors.jl and trying to resolve its problems
with respect to the latest Distributions.jl. As discussed in issue 11
<https://github.com/JuliaStats/ConjugatePriors.jl/issues/11>, testing
ConjugatePriors after removing the REQUIRE bounds results in:
MethodError: no method matching
_rand!(::Distributions.MvNormalCanon{PDMats.PDMat{Float64,Array{Float64,2}},Array{Float64,1}},
::Array{Float64,1}) on line 52 of conjugates_mvnormal.jl
<https://github.com/JuliaStats/ConjugatePriors.jl/blob/master/test/conjugates_mvnormal.jl#L52>.
and line 25 of fallbacks.jl
If you check that line you find the following:
posterior_randmodel(pri, G::IncompleteFormulation, x) = complete(G, pri,
posterior_rand(pri, G, x))
Okay, the problem isn't really there. The call to posterior_rand is inlined
(I assume), so it doesn't show up in the test stack trace. So we manually
go to:
posterior_rand(pri, G::IncompleteFormulation, x) = Base.rand(posterior_canon
(pri, G, x))
This also isn't the problem, at least not directly.
In fact, the also inlined call to posterior_canon(pri, G, x) works fine. It
returns an MvNormalCanon object and then Base.rand is called.
This calls some inlined functions, which eventually call
Base._rand!(MvNormalCanon, x::Vector), which leads to the problem, namely
that _rand!(MvNormalCannon, x::Matrix) is all that is defined.
But why was that so hard to discover? Why does only line 25 of fallbacks,jl
show up in the error stack trace? Was there a better way to debug this?
