From f6916774eea2ecc1262377cb14c2d494a0486358 Mon Sep 17 00:00:00 2001 From: Matthieu Sozeau Date: Sat, 29 Oct 2016 19:07:21 +0200 Subject: Do not shelve non-class subgoals but fail, it should be the instance writer's responsibility to not generated non-dependent non-class subgoals (otherwise we loose compatibility as shown in e.g. MathClasses, which goes into loops because of unexpectedly unconstrained goals). Reflect it in the doc. --- doc/refman/Classes.tex | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) (limited to 'doc/refman') diff --git a/doc/refman/Classes.tex b/doc/refman/Classes.tex index d6a553e1a8..58ae7191f8 100644 --- a/doc/refman/Classes.tex +++ b/doc/refman/Classes.tex @@ -392,11 +392,13 @@ than {\tt eauto} and {\tt auto}. The main differences are the following: backtracking on subgoals that are entirely independent. \item When called with no arguments, {\tt typeclasses eauto} uses the {\tt typeclass\_instances} database by default (instead of {\tt core}) - and will try to solve \emph{only} typeclass goals. Other subgoals are - automatically shelved and \emph{must be} resolved entirely when the - other typeclass subgoals are resolved or the proof search will fail - \emph{globally}, \emph{without} the possibility to find another - complete solution with no shelved subgoals. + and will try to solve \emph{only} typeclass goals. If some subgoal of + a hint/instance is non-dependent and not of class type, that hint + application will fail. Dependent subgoals are automatically shelved + and \emph{must be} resolved entirely when the other typeclass subgoals + are resolved or the proof search will fail \emph{globally}, + \emph{without} the possibility to find another complete solution with + no shelved subgoals. \emph{Note: } As of Coq 8.6, {\tt all:once (typeclasses eauto)} faithfully mimicks what happens during typeclass resolution when it is -- cgit v1.2.3