paredit/kill-one-at-pos when deleting word in string/comment is questionable

[lread]

Version
1.1.49

Platform
All

Symptom
kill-one-at-pos wants to kill a word w within a string/comment when w's col position spans requested col.

Reproduction

(require '[rewrite-clj.paredit :as pe]
         '[rewrite-clj.zip :as z])

;                 11111111112222
;        12345678901234567890123
(let [s "foo  ;   hello   world"
      zloc (z/of-string* s {:track-position? true})
      row 1]
  (for [col (range 1 (inc (count s)))]
    [(format "%02d" col)
     (-> zloc
         (pe/kill-one-at-pos {:row row :col col})
         (z/root-string))]))

Actual behavior

(let [s "foo  ;   hello   world"
      zloc (z/of-string* s {:track-position? true})
      row 1]
  (for [col (range 1 (inc (count s)))]
    [(format "%02d" col)
     (-> zloc
         (pe/kill-one-at-pos {:row row :col col})
         (z/root-string))]))
;; => (["01" ";   hello   world"]          good, we are in span of foo, so delete it
;;     ["02" ";   hello   world"]          "
;;     ["03" ";   hello   world"]          "
;;     ["04" "foo"]                        good, we search forward for the next non-ws none after col and delete it
;;     ["05" "foo"]                        "
;;     ["06" "foo"]                        good, we are at comment and delete it
;;     ["07" "foo  ;   hello   world"]     ok, guess if we are not within a word we do not delete it
;;     ["08" "foo  ;   hello   world"]     "
;;     ["09" "foo  ;      world"]          BAD, hello starts at col 10, but we've deleted it
;;     ["10" "foo  ;      world"]          good, we are within hello
;;     ["11" "foo  ;      world"]          "
;;     ["12" "foo  ;      world"]          "
;;     ["13" "foo  ;      world"]          "
;;     ["14" "foo  ;      world"]          "
;;     ["15" "foo  ;   hello   world"]     again, if we are between words, no-op
;;     ["16" "foo  ;   hello   world"]     "
;;     ["17" "foo  ;   hello   "]          BAD, world starts at 18
;;     ["18" "foo  ;   hello   "]
;;     ["19" "foo  ;   hello   "]
;;     ["20" "foo  ;   hello   "]
;;     ["21" "foo  ;   hello   "]
;;     ["22" "foo  ;   hello   "])

Expected behavior
If I study the code, I think the intent almost matches the above and we have an off-by-one-error.

See also
Killing a word within a string uses same algorithm and has same problem:

;                  111111111122 2
;        1234 56789012345678901 2
(let [s "foo \"   hello   world\""
      zloc (z/of-string* s {:track-position? true})
      row 1]
  (for [col (range 1 (inc (count s)))]
    [(format "%02d" col)
     (-> zloc
         (pe/kill-one-at-pos {:row row :col col})
         (z/root-string))]))
;; => (["01" "\"   hello   world\""]
;;     ["02" "\"   hello   world\""]
;;     ["03" "\"   hello   world\""]
;;     ["04" "foo"]
;;     ["05" "foo"]
;;     ["06" "foo \"   hello   world\""]
;;     ["07" "foo \"   hello   world\""]
;;     ["08" "foo \"      world\""]            BAD, hello starts at col 9 but we've deleted it
;;     ["09" "foo \"      world\""]
;;     ["10" "foo \"      world\""]
;;     ["11" "foo \"      world\""]
;;     ["12" "foo \"      world\""]
;;     ["13" "foo \"      world\""]
;;     ["14" "foo \"   hello   world\""]
;;     ["15" "foo \"   hello   world\""]
;;     ["16" "foo \"   hello   \""]           BAD, world starts at col 17 but we've deleted it
;;     ["17" "foo \"   hello   \""]
;;     ["18" "foo \"   hello   \""]
;;     ["19" "foo \"   hello   \""]
;;     ["20" "foo \"   hello   \""]
;;     ["21" "foo \"   hello   \""]
;;     ["22" "foo \"\""])

Diagnosis
My feeling is that this fn does too much.
Also I'm not sure of the general usefulness of kill-one-at-pos within a string/comment is:

• Its concept of a "word" is simplistic.
• It doesn't handle removing whitespace after the killed word.

Action
I'll fix the off-by-one error.
If folks try to use this fn and have difficulty we can raise a separate issue to try to addresss.