From c1af52e4ff204c12c7b7f871a8c007214fb44190 Mon Sep 17 00:00:00 2001 From: "simonpj@microsoft.com" Date: Tue, 5 Sep 2006 09:22:01 +0000 Subject: [PATCH] Add note about overlapping instances --- docs/users_guide/glasgow_exts.xml | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/docs/users_guide/glasgow_exts.xml b/docs/users_guide/glasgow_exts.xml index 0a9c7e8..19e1416 100644 --- a/docs/users_guide/glasgow_exts.xml +++ b/docs/users_guide/glasgow_exts.xml @@ -2194,8 +2194,20 @@ some other constraint. But if the instance declaration was compiled with check for that declaration. -All this makes it possible for a library author to design a library that relies on -overlapping instances without the library client having to know. +These rules make it possible for a library author to design a library that relies on +overlapping instances without the library client having to know. + + +If an instance declaration is compiled without +, +then that instance can never be overlapped. This could perhaps be +inconvenient. Perhaps the rule should instead say that the +overlapping instance declaration should be compiled in +this way, rather than the overlapped one. Perhaps overlap +at a usage site should be permitted regardless of how the instance declarations +are compiled, if the flag is +used at the usage site. (Mind you, the exact usage site can occasionally be +hard to pin down.) We are interested to receive feedback on these points. The flag implies the flag, but not vice versa. -- 1.7.10.4