And what if I'm searching through a large directory? Your response doesn't address the argument being made.

Creating an API where the entire set of data is returned from a data source, without an option to limit the result, is bad. It means that, if I have to read a directory with 2000 files (and this is quite possible! - think /bin, etc.) the function will have to allocate a slice with 2000 entries, and then call stat on all of them.

Stat is not free, especially on certain filesystems (NFS!), nor is reading directory entries.