Should better error messages be added to `inv`?

linearalgebra
#1

When I am using LinearAlgebra.inv, I found that the error message of it could be very primitive

julia> inv(zeros(3,3))
ERROR: LAPACKException(1)
Stacktrace:
 [1] chklapackerror at /Users/osx/buildbot/slave/package_osx64/build/usr/share/julia/stdlib/v1.1/LinearAlgebra/src/lapack.jl:38 [inlined]
 [2] trtrs!(::Char, ::Char, ::Char, ::Array{Float64,2}, ::Array{Float64,2}) at /Users/osx/buildbot/slave/package_osx64/build/usr/share/julia/stdlib/v1.1/LinearAlgebra/src/lapack.jl:3348
 [3] inv at /Users/osx/buildbot/slave/package_osx64/build/usr/share/julia/stdlib/v1.1/LinearAlgebra/src/triangular.jl:583 [inlined]
 [4] inv(::Array{Float64,2}) at /Users/osx/buildbot/slave/package_osx64/build/usr/share/julia/stdlib/v1.1/LinearAlgebra/src/dense.jl:728
 [5] top-level scope at none:0

julia> inv(A)
ERROR: SingularException(3)
Stacktrace:
 [1] checknonsingular at /Users/osx/buildbot/slave/package_osx64/build/usr/share/julia/stdlib/v1.1/LinearAlgebra/src/factorization.jl:12 [inlined]
 [2] #lu!#103(::Bool, ::Function, ::Array{Float64,2}, ::Val{true}) at /Users/osx/buildbot/slave/package_osx64/build/usr/share/julia/stdlib/v1.1/LinearAlgebra/src/lu.jl:41
 [3] #lu! at ./none:0 [inlined]
 [4] #lu#107 at /Users/osx/buildbot/slave/package_osx64/build/usr/share/julia/stdlib/v1.1/LinearAlgebra/src/lu.jl:142 [inlined]
 [5] lu at /Users/osx/buildbot/slave/package_osx64/build/usr/share/julia/stdlib/v1.1/LinearAlgebra/src/lu.jl:142 [inlined] (repeats 2 times)
 [6] inv(::Array{Int64,2}) at /Users/osx/buildbot/slave/package_osx64/build/usr/share/julia/stdlib/v1.1/LinearAlgebra/src/dense.jl:732
 [7] top-level scope at none:0

Of course, the examples I gave are straightforward and can be pinpointed quickly. But if such error occurs at the midpoint of a calculation, wouldn’t it let users try hard to debug?

#2

Something related was discussed in

and adding nice Base.showerror methods would surely help. Please make a PR if you can.

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