POSIX allows blank characters before '!', but not after.
Reported-by: <onf@disroot.org>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
sed -E '/\/intro./ s/.*\.([[:digit:]])$/\10\t&/' \
| sed -E '/\/intro./ s/.*\.([[:digit:]])([[:alpha:]][[:alnum:]]*\>)/\12.\20\t&/' \
-| sed -E '/\/intro./! s/.*\.([[:digit:]])\>/\11\t&/' \
-| sed -E '/\/intro./! s/.*\.([[:digit:]])([[:alpha:]][[:alnum:]]*\>)/\12.\21\t&/' \
+| sed -E '/\/intro./ !s/.*\.([[:digit:]])\>/\11\t&/' \
+| sed -E '/\/intro./ !s/.*\.([[:digit:]])([[:alpha:]][[:alnum:]]*\>)/\12.\21\t&/' \
| sed -E ' s/\t(.*)/&\n\1/' \
| sed -E '/\t/ s/\.[[:digit:]]([[:alpha:]][[:alnum:]]*)?\>.*//' \
| sed -E '/\t/ s/\/[_-]*/\//g' \