bash - Sed delete lines with more than one word, excluding a search term -

bash - Sed delete lines with more than one word, excluding a search term -

i'm trying write sed command search file, , delete lines in file have more 1 word. however, need exclude deleting line starts particular symbol (going "[")

this have far (this not including code exclude line, delete lines more 1 word):

sed -e '/^\s*\s+\s*$/!d' $1

i wanted go exclude searching lines start left bracket ("["):

sed -e '/a/!d/^\s*\s+\s*$/!d' $1

however, i'm getting error:

sed: -e look #1, char 6: characters after command

i'm sure it's little , ridiculous i'm missing. able help out this? cheers.

an awk command simpler:

awk 'nf<2 || /(^| )\[/' file

this awk print lines have less 2 words or word starting [

bash unix sed