how to use grep to match with either whitespace or newline

Question

I want to grep a file with a word, say \"AAA\", and it ends with whitespace or newlines. I know how to write this seperately, as follows, but having problems in combining th

Answer 1

Use "AAA\b" if it's acceptable to also match AAA followed by any other non-alphanumeric character. According to the grep man pages, \b matches the empty string at the edge of a word.

$ echo -e "AAA VVV \nVVV AAA\nBBB" | grep "AAA\b"
AAA VVV
VVV AAA