PowerQuery递归

用递归思维将 "abcdefg" 转换成 "a-b-c-d-e-f-g"

let
    fx = (n) => if Text.Length(n) <= 1 then  n  else @fx(Text.Start(n,Text.Length(n)-1))&"-"&Text.Middle(n,Text.Length(n)-1,1) 
in
    fx("adfg")