<div dir="auto">The most common legitimate usage for undefined I have is strictness:<div dir="auto"><br></div><div dir="auto">func x y | x `seq` False = undefined</div><div dir="auto">func x y = ...</div><div dir="auto"><br></div><div dir="auto">There's nothing else that would go there, and when it's compiled, the reference to undefined disappears.</div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Sun, Dec 22, 2019, 05:50 chessai . <<a href="mailto:chessai1996@gmail.com">chessai1996@gmail.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="auto">Right, it's been discussed before IIRC, and i know I've certainly given it passing thoughts. I think this isn't worth it because of breakage. Many people use -Wall -Werror, so I see this as a no-go.<div dir="auto"><br></div><div dir="auto">Thanka</div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Sun, Dec 22, 2019, 6:45 AM Vilem Liepelt <<a href="mailto:vliepelt@futurefinance.com" target="_blank" rel="noreferrer">vliepelt@futurefinance.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Has there been any discussion about adding WARNING pragmas to `Prelude.undefined` and `Prelude.error`, as done in some custom preludes?<br>
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I suppose this hasn't been done yet to avoid breaking existing code which makes "legitimate" use of those helpers?<br>
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