TODO notes for change to allow new config fields

TODO.md

@@ -1,7 +1,37 @@
+# higher prio
+
 - `bunyan` (without redir) ^C should stop, doesn't since recent change
 - man page for the bunyan CLI (refer to it in the readme)
-- `tail -f`-like support
-- 2.0 (?) with `v: 1` in log records. Fwd/bwd compat in `bunyan` CLI
+
+
+# changes to ctor and log.child to separate fields from config
+
+Current:
+    createLogger(<config-and-fields>)
+    log.child(<config-and-fields>, <just-fields-bool>)
+
+Could be:
+    createLogger(<config-and-fields>, <fields>)
+    log.child(<config-and-fields>, <fields>)
+        # Still support: log.child(<config-and-fields>, <just-fields-bool>)
+
+Pros: Compat issues are minimal: a change is only required if there is a
+collision with used field and a new config var name.
+Cons: A *slight* con is that my guess is the common usage of child is
+`log.child(<fields>)`, so the more future-proof common usage becomes:
+    log.child(null, <fields>)
+That's not too bad. It is clearer at least than:
+    log.child(<fields>, true)
+
+TODO:
+- is there a ticket for this work already?
+- make the change
+- do a migration guide? i.e. provide the grep commands to find all
+  possible calls to inspect. E.g. if don't have `rg logUndefined` in your
+  code, then you are fine. And one time future-proofing via changing
+  to fields in the *second* arg.
+- list of issues/pulls that wanted to add new config fields
+
 
 # docs
 
@@ -10,6 +40,8 @@
 
 # someday/maybe
 
+- 2.0 (?) with `v: 1` in log records. Fwd/bwd compat in `bunyan` CLI
+- `tail -f`-like support
 - full-on docs
 - better examples/
 - better coloring