Move line 35 to line 1:

[YONGTEENFOH]

$echo "$(sed -n '35p' editme.txt)"+"$(sed -n '1,34p;36,38p' editme.txt)" > editme.txt

$cat editme.txt
35+1
2
3
4
5
6
...

it appends line 35 to line 1

[giulianopz]

Fixed with commit #4a46c7ae682cb6d0e535de3be846e85134b31749