totan can mean .. surutosuguni (するとすぎに） or it mean that after we doing A we doing B, it's simple grammar but something that must remember is that before totan (とたん) is always Verb.ta form, look at simple formula below
V.ta + Totan
after that
todan, is also intermediate grammar for JLPT (Japan Language Proficiency Test) level 2,
here some example sentence using totan
彼女は 部屋を入ったとたん ご飯を 食べた。
kanojyo ha heya wo haita totan gohan wo taberu
she eeting rice after enter the room
dia setelah masuk kamar langsung makan
外へ出たとたん、雨が 降りました。
soto he deta totan ame ga furimashita.
while gone to out side the rain come.
hujan turun begitu keluar.
i think 2 example is enough, becouse ta totan is not very difficult
V.ta + Totan
after that
todan, is also intermediate grammar for JLPT (Japan Language Proficiency Test) level 2,
here some example sentence using totan
彼女は 部屋を入ったとたん ご飯を 食べた。
kanojyo ha heya wo haita totan gohan wo taberu
she eeting rice after enter the room
dia setelah masuk kamar langsung makan
外へ出たとたん、雨が 降りました。
soto he deta totan ame ga furimashita.
while gone to out side the rain come.
hujan turun begitu keluar.
i think 2 example is enough, becouse ta totan is not very difficult