How to I add something to the .gitignore so that the match is not recursive?

Question

How to I add something to the .gitignore so that the match is not recursive?

For example, I wish to ignore the directory foo and the file

Answer 1

The solution is to place a leading slash on the .gitignore entries:

/foo/
/bar.txt

(I thought I tried this before posting on StackOverflow, but clearly I hadn't tried it properly, as this works perfectly.)