Inconsistency is a much lesser problem than incompatibility. Two modules defining different instances for the same class and type can't be used together. And if you force one instance out of the picture with a command line parameter, you better prepare for some VERY unexpected results.<br /><br /><div>04.02.2016, 12:48, "Imants Cekusins" &lt;imantc@gmail.com&gt;:</div><blockquote type="cite"><div><p>if Show is the opposite of Read, then serialization is probably the<br />purpose, consistency is more important.<br /><br /><br />re: formatting GHCi output:<br /><br />what if GHCi used another class (not Show) for formatting output?<br /><br />what if it were possible to pass a cmd flag to ghci to specify<br />formatting instance to use in this session?<br />_______________________________________________<br />Haskell-Cafe mailing list<br /><a>Haskell-Cafe@haskell.org</a><br /><a href="http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe" data-vdir-href="http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe" data-orig-href="http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe" target="_blank">http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-caf…</a><br /></p></div></blockquote><div><br /></div><div><br /></div><div></div><div><br /></div>