exception on writing maps where a key is a map

[flyingmachine]

This:

(charred.api/write-json-str {{:a :b} {:c :d}})

Results in this:

Execution error (CharredException) at charred.JSONWriter/writeMap (JSONWriter.java:189).
JSON encoding error - Map keys must be strings

My expectation is that {:a :b} would be stringified. It's not immediately obvious to me how to work around this

[cnuernber]

Well that won't round trip -- but neither do keyword map keys -- I agree that it should apply str as opposed to exception.