some printing upgrades

src/layers/show.jl

@@ -14,13 +14,13 @@ for T in [
 end
 
 function _big_show(io::IO, obj, indent::Int=0, name=nothing)
-  pre, post = obj isa Chain{<:AbstractVector} ? ("([", "])") : ("(", ")")
+  pre, post = _show_pre_post(obj)
   children = _show_children(obj)
   if all(_show_leaflike, children)
     _layer_show(io, obj, indent, name)
   else
-    println(io, " "^indent, isnothing(name) ? "" : "$name = ", nameof(typeof(obj)), pre)
-    if obj isa Chain{<:NamedTuple} && children == getfield(obj, :layers)
+    println(io, " "^indent, isnothing(name) ? "" : "$name = ", pre)
+    if obj isa Chain{<:NamedTuple} || obj isa NamedTuple
       # then we insert names -- can this be done more generically? 
       for k in Base.keys(obj)
         _big_show(io, obj[k], indent+2, k)
@@ -44,6 +44,11 @@ function _big_show(io::IO, obj, indent::Int=0, name=nothing)
   end
 end
 
+_show_pre_post(obj) = string(nameof(typeof(obj)), "("), ")"
+_show_pre_post(::Chain{<:AbstractVector}) = "Chain([", "])"
+_show_pre_post(::AbstractVector) = "[", "]"
+_show_pre_post(::NamedTuple) = "(;", ")"
+
 _show_leaflike(x) = isleaf(x)  # mostly follow Functors, except for:
 
 # note the covariance of tuple, using <:T causes warning or error
@@ -73,7 +78,7 @@ end
 
 function _layer_show(io::IO, layer, indent::Int=0, name=nothing)
   _str = isnothing(name) ? "" : "$name = "
-  str = _str * sprint(show, layer, context=io)
+  str = _str * _layer_string(io, layer)
   print(io, " "^indent, str, indent==0 ? "" : ",")
   if !isempty(params(layer))
     print(io, " "^max(2, (indent==0 ? 20 : 39) - indent - length(str)))
@@ -88,6 +93,12 @@ color=:light_black)
   indent==0 || println(io)
 end
 
+_layer_string(io::IO, layer) = sprint(show, layer, context=io)
+# _layer_string(::IO, a::AbstractArray) = summary(layer)  # sometimes too long e.g. CuArray
+# _layer_string(::IO, a::AbstractArray) = Base.dims2string(size(a)) * " " * String(typeof(a).name.name)
+# _layer_string(::IO, a::Array{T}) where T = Base.dims2string(size(a)) * " Array{$T}"
+# _layer_string(::IO, a::AbstractArray{T}) where T = Base.dims2string(size(a)) * " AbstractArray{$T}"
+
 function _big_finale(io::IO, m)
   ps = params(m)
   if length(ps) > 2
@@ -133,3 +144,43 @@ _any(f, x::Number) = f(x)
 # _any(f, x) = false
 
 _all(f, xs) = !_any(!f, xs)
+
+#=
+
+julia> struct Tmp2; x; y; end; Flux.@functor Tmp2
+
+# Before, notice Array(), NamedTuple(), and values
+
+julia> Chain(Tmp2([Dense(2,3), randn(3,4)'], (x=1:3, y=Dense(3,4), z=rand(3))))
+Chain(
+  Tmp2(
+    Array(
+      Dense(2 => 3),                    # 9 parameters
+      [0.351978391016603 0.6408681372462821 -1.326533184688648; 0.09481930831795712 1.430103476272605 0.7250467613675332; 2.03372151428719 -0.015879812799495713 1.9499692162118236; -1.6346846180722918 -0.8364610153059454 -1.2907265737483433],  # 12 parameters
+    ),
+    NamedTuple(
+      1:3,                              # 3 parameters
+      Dense(3 => 4),                    # 16 parameters
+      [0.9666158193429335, 0.01613900990539574, 0.0205920186127464],  # 3 parameters
+    ),
+  ),
+)                   # Total: 7 arrays, 43 parameters, 644 bytes.
+
+# After, (; x=, y=, z=) and "3-element Array"
+
+julia> Chain(Tmp2([Dense(2,3), randn(3,4)'], (x=1:3, y=Dense(3,4), z=rand(3))))
+Chain(
+  Tmp2(
+    [
+      Dense(2 => 3),                    # 9 parameters
+      4×3 Adjoint,                      # 12 parameters
+    ],
+    (;
+      x = 3-element UnitRange,          # 3 parameters
+      y = Dense(3 => 4),                # 16 parameters
+      z = 3-element Array,              # 3 parameters
+    ),
+  ),
+)                   # Total: 7 arrays, 43 parameters, 644 bytes.
+
+=#