what are some example case of files needing newline at end?

[Xah Lee]

what are some examples of files that requires a newline by itself at
the end?

Detail:

recently i'm coding elisp to process a input file line by line. Each
line is expected to have text.
I ran into error at the last line because the file has a empty line,
and i noticed that it is automatically added, due to mode-require-
final-newline being true.

So, i'm wondering, what kinda files actually require newline at the
end? and if it is still so today?

  Xah
∑ http://xahlee.org/

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