[mod] pr-signal: switch to single (opts) arity only

For consistency with other utils and handlers

examples.cljc

@@ -141,7 +141,7 @@
 ;; Create console which writes signals as edn
 (def my-handler
   (t/handler:console
-    {:output-fn (t/pr-signal-fn :edn)}))
+    {:output-fn (t/pr-signal-fn {:pr-fn :edn})}))
 
 (my-handler my-signal) ; =>
 ;; {:inst #inst "2024-04-11T10:54:57.202869Z", :msg_ "My message", :ns "examples", ...}
@@ -152,8 +152,9 @@
   (t/handler:console
     {:output-fn
      (t/pr-signal-fn
+       {:pr-fn
         #?(:cljs :json
-          :clj  jsonista.core/write-value-as-string))}))
+           :clj  jsonista.core/write-value-as-string)})}))
 
 (my-handler my-signal) ; =>
 ;; {"inst":"2024-04-11T10:54:57.202869Z","msg_":"My message","ns":"examples", ...}

src/taoensso/telemere/utils.cljc

@@ -582,26 +582,27 @@
     - Returns a machine-readable (minified) signal string.
 
   Options:
-    `pr-fn`          - ∈ #{<unary-fn> :edn :json (Cljs only)}
+    `:pr-fn`         - ∈ #{<unary-fn> :edn (default) :json (Cljs only)}
     `:incl-thread?`  - Include signal `:thread` info?      (default false)
     `:incl-kvs?`     - Include signal `:kvs`    info?      (default false)
     `:incl-newline?` - Include terminating system newline? (default true)
 
   Examples:
-    (pr-signal-fn :edn  {<opts>})
+    (pr-signal-fn {:pr-fn :edn  ...}) ; Outputs edn
-    (pr-signal-fn :json {<opts>}) ; Cljs only
+    (pr-signal-fn {:pr-fn :json ...}) ; Outputs JSON (Cljs only)
+
+    To output JSON for Clj, you must provide an appropriate `:pr-fn`.
+    `jsonista` is one good option, Ref. <https://github.com/metosin/jsonista>:
 
-    ;; To output JSON for Clj, you must provide an appropriate `pr-fn`.
-    ;; `jsonista` is a good option, Ref. <https://github.com/metosin/jsonista>:
       (require '[jsonista.core :as jsonista])
-      (pr-signal-fn jsonista/write-value-as-string {<opts>})
+      (pr-signal-fn {:pr-fn jsonista/write-value-as-string ...})
 
   See also `format-signal-fn` for human-readable output."
-  ([pr-fn] (pr-signal-fn pr-fn nil))
+  ([] (pr-signal-fn nil))
-  ([pr-fn
+  ([{:keys [incl-thread? incl-kvs? incl-newline?, pr-fn prep-fn]
-    {:keys [incl-thread? incl-kvs? incl-newline?, prep-fn]
      :or
      {incl-newline? true
+      pr-fn         :edn
       prep-fn
       (comp error-in-signal->maps
         minify-signal)}}]
@@ -611,7 +612,12 @@
          (or
            (case  pr-fn
              :edn pr-edn
-             #?@(:cljs [:json pr-json])
+             :json
+             #?(:cljs pr-json
+                :clj
+                (throw
+                  (ex-info "`:json` pr-fn only supported in Cljs. To output JSON in Clj, please provide an appropriate unary fn instead (e.g. jsonista/write-value-as-string)."
+                    {})))
 
              (if (fn? pr-fn)
                (do    pr-fn)
@@ -634,8 +640,8 @@
            (do  output)))))))
 
 (comment
-  ((pr-signal-fn :edn)           (tel/with-signal (tel/event! ::ev-id {:kvs {:k1 "v1"}})))
+  ((pr-signal-fn {:pr-fn :edn})           (tel/with-signal (tel/event! ::ev-id {:kvs {:k1 "v1"}})))
-  ((pr-signal-fn (fn [_] "str")) (tel/with-signal (tel/event! ::ev-id {:kvs {:k1 "v1"}}))))
+  ((pr-signal-fn {:pr-fn (fn [_] "str")}) (tel/with-signal (tel/event! ::ev-id {:kvs {:k1 "v1"}}))))
 
 (defn format-signal-fn
   "Experimental, subject to change.

test/taoensso/telemere_tests.cljc

@@ -691,18 +691,21 @@
 
          [(testing ":edn"
             (let [sig   (update sig :inst enc/inst->udt)
-                  sig* (enc/read-edn ((tel/pr-signal-fn :edn) sig))]
+                  sig*1 (enc/read-edn ((tel/pr-signal-fn {:pr-fn :edn}) sig))
+                  sig*2 (enc/read-edn ((tel/pr-signal-fn)               sig))]
+
+              [(is (= sig*1 sig*2) "Default :pr-fn is :edn")
                (is
-                (enc/submap? sig*
+                 (enc/submap? sig*1
                    {:schema 1, :kind :event, :id ::ev-id, :level :info,
                     :ns      "taoensso.telemere-tests"
                     :inst    udt0
                     :line    pnat-int?
-                   :column  pnat-int?}))))
+                    :column  pnat-int?}))]))
 
           #?(:cljs
              (testing ":json"
-               (let [sig* (enc/read-json ((tel/pr-signal-fn :json) sig))]
+               (let [sig* (enc/read-json ((tel/pr-signal-fn {:pr-fn :json}) sig))]
                  (is
                    (enc/submap? sig*
                      {"schema" 1, "kind" "event", "id" "taoensso.telemere-tests/ev-id",
@@ -712,7 +715,7 @@
                       "column"  pnat-int?})))))
 
           (testing "user fn"
-            (is (= ((tel/pr-signal-fn (fn [_] "str")) sig) (str "str" utils/newline))))]))
+            (is (= ((tel/pr-signal-fn {:pr-fn (fn [_] "str")}) sig) (str "str" utils/newline))))]))
 
       (testing "format-signal-fn"
         (let [sig (with-sig (tel/event! ::ev-id {:inst t0}))]

wiki/4-Handlers.md

@@ -76,7 +76,7 @@ To instead writes signals as edn:
 ;; Create console which writes edn
 (def my-handler
   (t/handler:console
-    {:output-fn (t/pr-signal-fn :edn)}))
+    {:output-fn (t/pr-signal-fn {:pr-fn :edn})}))
 
 (my-handler my-signal) ; =>
 ;; {:inst #inst "2024-04-11T10:54:57.202869Z", :msg_ "My message", :ns "examples", ...}
@@ -91,8 +91,9 @@ To instead writes signals as JSON:
   (t/handler:console
     {:output-fn
      (t/pr-signal-fn
+       {:pr-fn
         #?(:cljs :json
-          :clj  jsonista.core/write-value-as-string))}))
+           :clj  jsonista.core/write-value-as-string)})}))
 ```
 
 Note that when writing JSON with Clojure, you *must* provide an appropriate `pr-fn`. This lets you plug in the JSON serializer of your choice ([jsonista](https://github.com/metosin/jsonista) is my default recommendation).