For a 1.9.1 release

Project.toml

@@ -1,7 +1,7 @@
 name = "MLJBase"
 uuid = "a7f614a8-145f-11e9-1d2a-a57a1082229d"
 authors = ["Anthony D. Blaom <[email protected]>"]
-version = "1.9.0"
+version = "1.9.1"
 
 [deps]
 CategoricalArrays = "324d7699-5711-5eae-9e2f-1d82baa6b597"

src/machines.jl

@@ -583,17 +583,17 @@ or none of the following apply:
 4. The specified `rows` have changed since the last retraining and
    `mach.model` does not have `Static` type.
 
-5. `mach.model` is a model and different from the last model used for training, but has
-   the same type.
+5. `mach.model` is a `Model` (i.e, not a symbol) and is different from the last model used
+   for training (but has the same type).
 
-6. `mach.model` is a model but has a type different from the last model used for
+6. `mach.model` is a `Model` but has a type different from the last model used for
    training.
 
-7. `mach.model` is a symbol and `(composite, mach.model)` is different from the last
-   model used for training, but has the same type.
+7. `mach.model` is a symbol and `getproperty(composite, mach.model)` is different from the
+   last model used for training (but has the same type).
 
-8. `mach.model` is a symbol and `(composite, mach.model)` has a different type from
-   the last model used for training.
+8. `mach.model` is a symbol and `getproperty(composite, mach.model)` has a different type
+   from the last model used for training.
 
 In any of the cases (1) - (4), (6), or (8), `mach` is trained ab initio.
 If (5) or (7) is true, then a training update is applied.
@@ -645,6 +645,7 @@ function fit_only!(
         mach.model
     end
 
+    # neither `old_model` nor `model` are symbols here:
     modeltype_changed = !isdefined(mach, :old_model) ? true  :
             typeof(model) === typeof(mach.old_model) ? false :
                                                        true

src/show.jl

@@ -78,32 +78,6 @@ function handle(X)
 end
 
 
-## SHOW METHOD FOR NAMED TUPLES
-
-# long version of showing a named tuple:
-Base.show(stream::IO, ::MIME"text/plain", t::NamedTuple) = fancy_nt(stream, t)
-fancy_nt(t) = fancy_nt(stdout, t) # is this used?
-fancy_nt(stream, t::NamedTuple{(), Tuple{}}) = print(stream, "NamedTuple()")
-fancy_nt(stream, t) = fancy_nt(stream, t, 0)
-fancy_nt(stream, t, n) = show(stream, t)
-function fancy_nt(stream, t::NamedTuple, n)
-    print(stream, "(")
-    first_item = true
-    for k in keys(t)
-        value =  getproperty(t, k)
-        if !first_item
-            print(stream, crind(n + 1))
-        else
-            first_item = false
-        end
-        print(stream, "$k = ")
-        fancy_nt(stream, value, n + length("$k = ") + 1)
-        print(stream, ",")
-    end
-    print(stream, ")")
-end
-
-
 ## OTHER EXPOSED SHOW METHODS
 
 # string consisting of carriage return followed by indentation of length n: