ok or true?

Robert Virding <>
Mon Feb 23 23:07:00 CET 2004


----- Original Message ----- 
From: "Vance Shipley" <>
Sent: Sunday, February 22, 2004 8:02 PM
Subject: Re: ok or true?

> I would expect a function which returns true to have only
> one other possible return value; false.  It is my observation
> that most functions which always succeed return true.  I
> would find a function which returned true or {error, Reason}
> to be quite odd.

Correct. True and false are boolean values and should only be returned if
the return value is a boolean value. Otherwise use ok and error/{error,...}.
It was a bad design decision that many BIFs and library functions return
true or false to signify success and error. We weren't thinking straight
when we did that.

Robert




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