Haskellのdoctest (ghci) の:{..:}中のletでincorrect indentation
こんな感じのdoctestを書いていると怒られた 😭
-- >>> :{
-- >>> let result = "good"
-- >>> "good"
-- >>> :}
-- "good"### Failure in Foo.hs:364: expression `:{
let result = "good"
"good"
:}'
expected: "good"
but got:
<interactive>:436:2: error:
parse error (possibly incorrect indentation or mismatched brackets)let式を使うと（letにinを付けると）正しく実行された。
-- >>> :{
-- >>> let result = "good" in
-- >>> "good"
-- >>> :}
-- "good"ちなみにこれもだめだった 😕
-- >>> :{
-- >>> let result = "good"
-- >>> return "good"
-- >>> :}
-- "good"マジかよ ❗ ❗
参考までに、以下は「こんな感じ」の実例。
-- >>> :{
-- >>> let result = [z|
-- >>> (do
-- >>> (def! x 10)
-- >>> (def! y (+ 10 x))
-- >>> (fn* (a) (+ x y)))
-- >>> |] in
-- >>> case result of
-- >>> [pp|(fn* (a) (+ 10 20))|] -> "good"
-- >>> _ -> "bad: " <> readable result
-- >>> :}
-- "good"### Failure in src/Maru/Eval.hs:364: expression `:{ilures: 0
let result = [z|
(do
(def! x 10)
(def! y (+ 10 x))
(fn* (a) (+ x y)))
|]
case result of
[pp|(fn* (a) (+ 10 20))|] -> "good"
_ -> "bad: " <> readable result
:}'
expected: "good"
but got:
<interactive>:441:2: error:
parse error (possibly incorrect indentation or mismatched brackets)