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It was thus said that the Great Andrew Starks once stated:
> On Thursday, January 15, 2015, Tim Hill <> wrote:
> I think it might be useful to reserve the word "error" for "things that
> disrupt the stack" and something like "fail" for a return value that
> indicates the function's failure to return a result.

  I go into some detail about this in my blog:

  I classify errors into four types (one of which could be considered "a
bug") and I mention there are only three ways to handling them.

> Thinking about something in a different way has implications. If we stop
> conflating exceptional return values ;) by calling them "errors", it may
> help clarify their roll.

  Lisp people talk about "conditions", not "errors".  

> open_file"foo"
> -->false, "NO 'foo'"
> read_next_chunk()
> -->nil, "TIMEOUT"
> Both of these make sense to me and would make less sense to me if they were
> reversed. Also, neither are errors in programming or in the system. As far
> as the context of the program is concerned, neither are errors, at all.

  But both can be handled the same way:

	fp,err = open_file "foo"
	if not fp then

	data,err = read_next_chunk()
	if not data then

but only because nil and false are falsey values.