Fix clerk stats viewer npe

notebooks/missing_id_repro.clj

@@ -0,0 +1,23 @@
+;; # 🐞Missing ID Repro
+(ns missing-id-repro
+  {:nextjournal.clerk/no-cache true}
+  (:require [nextjournal.clerk :as clerk]))
+
+(def pred-viewer
+  {:pred :a/b
+   :transform-fn (fn [{:as wv :keys [id path]}]
+                   (prn :matching id :path path)
+                   #_ (when-not id (throw (ex-info "No ID" {:wrapped-value wv})))
+                   wv)
+   :render-fn '(fn [_ _] [:em "test"])})
+
+(clerk/add-viewers! [pred-viewer])
+
+;; cell-id is only present for values matching top-level forms, all matching values
+;; at deeper paths won't have an id.
+
+{:a/b 1
+ :children [{:a/b 2}]}
+
+(comment
+  (-> (ex-data *e) :wrapped-value :path))

notebooks/nested_tabular_data.clj

@@ -0,0 +1,25 @@
+(ns nested-tabular-data
+  {:nextjournal.clerk/visibility {:code :hide :result :hide}
+   :nextjournal.clerk/no-cache true}
+  (:require [nextjournal.clerk :as clerk]
+            [nextjournal.clerk-table-stats :as clerk-table-stats]))
+
+#_(clerk/add-viewers! [])
+(clerk/add-viewers! [clerk-table-stats/view-as-table-viewer
+                     clerk-table-stats/viewer])
+
+{:nextjournal.clerk/visibility {:code :hide :result :show}}
+
+[{:category :bang
+  :value 11}
+ {:category :barx
+  :value 20}
+ {:category :bug
+  :value 22
+  :children [{:category :bang :value 11}
+             {:category :barx :value 20}]}]
+
+[(sorted-map "one" 1 "two" 2)
+ (sorted-map "one" 1 "two" 2)
+ (sorted-map "one" 1 "two" 2)
+ (sorted-map "one" 1 "two" 2)]

src/nextjournal/clerk_table_stats.clj

@@ -535,6 +535,34 @@
                              (nextjournal.clerk.render/inspect-presented opts cell)]))
                          row)))})
 
+(defn tabular? [xs]
+  (and (seqable? xs)
+       (sequential? xs)
+       (let [sample (take 100 xs)]
+         ;; TODO: do we also need some normalization to be successful?
+         ;; normalize-seq-of-map currently always returns truthy on a seq of maps
+         (every? map? sample))))
+
+{::clerk/render-opts {:group-headers true}
+ ::clerk/page-size 5
+ ::clerk/width :full}
+
+(def view-as-table-viewer
+  ;; TODO: decide if we want to opt out of matching only top-level forms
+  {:pred {:wrapped (every-pred (comp #{1} count (viewer/get-safe :path))
+                               (comp tabular? viewer/->value))}
+   :transform-fn (partial clerk/with-viewer 'nextjournal.clerk.viewer/table-viewer)})
+
+;; usage with default global options
+(comment
+  (update view-as-table-viewer
+          :transform-fn
+          (fn [f]
+            (fn [wv]
+              (f {::clerk/render-opts {:group-headers true}
+                  ::clerk/page-size 5
+                  ::clerk/width :full} wv)))))
+
 (def viewer
   (assoc viewer/table-viewer
          :transform-fn