Also make symbol actionable to open in source file

Author: xenodium

helpful.el

@@ -2043,17 +2043,17 @@ OBJ may be a symbol or a compiled function object."
             ((macrop sym) "macro")
             ((helpful--kbd-macro-p sym) keyboard-macro-button)
             (t "function")))
+          (path (buffer-file-name buf))
           (defined
             (cond
              (buf
-              (let ((path (buffer-file-name buf)))
-                (if path
+              (if path
                     (format
                      "defined in %s"
                      (helpful--navigate-button
                       (file-name-nondirectory path) path pos))
                   (format "defined in buffer %s"
-                          (helpful--buffer-button buf pos)))))
+                          (helpful--buffer-button buf pos))))
              (primitive-p
               "defined in C source code")
              ((helpful--kbd-macro-p sym) nil)
@@ -2064,7 +2064,10 @@ OBJ may be a symbol or a compiled function object."
      70
      (format "%s is %s %s %s%s."
              (if (symbolp sym)
-                 (helpful--format-symbol sym)
+                 (if path
+                     (helpful--navigate-button
+                      (helpful--format-symbol sym) path pos)
+                   (helpful--format-symbol sym))
                "This lambda")
              (if (string-match-p
                   (rx bos (or "a" "e" "i" "o" "u"))