Feature request: only print types once in an expression

As an example, consider the following snippet:

copy(M::ArrayLayouts.MulAdd) @ ArrayLayouts ~/Dropbox/JuliaPackages/ArrayLayouts.jl/src/muladd.jl:72
72 copy(M::ArrayLayouts.MulAdd{BlockArrays.BlockLayout{ArrayLayouts.DenseColumnMajor, ArrayLayouts.UnknownLayout}, BlockArrays.BlockLayout{ArrayLayouts.DenseColumnMajor, ArrayLayouts.DenseColumnMajor}, ArrayLayouts.ZerosLayout, Float64, BlockMatrix{Float64, Matrix{SparseMatrixCSC{Float64, Int64}}, Tuple{BlockedUnitRange{Vector{Int64}}, BlockedUnitRange{Vector{Int64}}}}, BlockVector{Float64, Vector{Vector{Float64}}, Tuple{BlockedUnitRange{Vector{Int64}}}}, FillArrays.Zeros{Float64, 1, Tuple{BlockedUnitRange{Vector{Int64}}}}}::MulAdd)::BlockVector{Float64, Vector{Vector{Float64}}, Tuple{BlockedUnitRange{Vector{Int64}}}} = copyto!(similar(M::ArrayLayouts.MulAdd{BlockArrays.BlockLayout{ArrayLayouts.DenseColumnMajor, ArrayLayouts.UnknownLayout}, BlockArrays.BlockLayout{ArrayLayouts.DenseColumnMajor, ArrayLayouts.DenseColumnMajor}, ArrayLayouts.ZerosLayout, Float64, BlockMatrix{Float64, Matrix{SparseMatrixCSC{Float64, Int64}}, Tuple{BlockedUnitRange{Vector{Int64}}, BlockedUnitRange{Vector{Int64}}}}, BlockVector{Float64, Vector{Vector{Float64}}, Tuple{BlockedUnitRange{Vector{Int64}}}}, FillArrays.Zeros{Float64, 1, Tuple{BlockedUnitRange{Vector{Int64}}}}})::BlockVector{Float64, Vector{Vector{Float64}}, Tuple{BlockedUnitRange{Vector{Int64}}}}, M::ArrayLayouts.MulAdd{BlockArrays.BlockLayout{ArrayLayouts.DenseColumnMajor, ArrayLayouts.UnknownLayout}, BlockArrays.BlockLayout{ArrayLayouts.DenseColumnMajor, ArrayLayouts.DenseColumnMajor}, ArrayLayouts.ZerosLayout, Float64, BlockMatrix{Float64, Matrix{SparseMatrixCSC{Float64, Int64}}, Tuple{BlockedUnitRange{Vector{Int64}}, BlockedUnitRange{Vector{Int64}}}}, BlockVector{Float64, Vector{Vector{Float64}}, Tuple{BlockedUnitRange{Vector{Int64}}}}, FillArrays.Zeros{Float64, 1, Tuple{BlockedUnitRange{Vector{Int64}}}}})
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 • similar(M::ArrayLayouts.MulAdd{BlockArrays.BlockLayout{ArrayLayouts.DenseColumnMajor, ArrayLayouts.UnknownLayout}, BlockArrays.BlockLayout{ArrayLayouts.DenseColumnMajor, ArrayLayouts.…
   copyto!(similar(M::ArrayLayouts.MulAdd{BlockArrays.BlockLayout{ArrayLayouts.DenseColumnMajor, ArrayLayouts.UnknownLayout}, BlockArrays.BlockLayout{ArrayLayouts.DenseColumnMajor, Array…
   ↩

Here, the source for line 72 reads

copy(M::MulAdd) = copyto!(similar(M), M)

and the type of M is printed beside each instance. This seems redundant and is not adding any additional information, but is significantly adding to visual clutter. I wonder if it might be possible to ensure that the types of variables are printed only once, perhaps when the variable occurs in an expression for the first time?

Start from the type-annotated expression display shown in the issue and trace how the debugger renders repeated variable types. Define the expected output for the example so each variable type is shown only on its first occurrence, then verify the revised display preserves the existing navigation and annotation controls.