reducer functions are called with coerced input

```clojure
(-> (a/interpose-$ :conj (vec "abc"))
    (a/compile {:reducers {:conj conj}})
    (a/find [] (seq "abc"))
    :value)
;=> [97 98 99]

(-> (a/interpose-$ :conj [\a :b "c"])
    (a/compile {:reducers {:conj conj}})
    (a/find [] [\a :b "c"])
    :value)
;=> [97 :b]
```

I don't know why `99`/`"c"` is missing in the second example.