id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	os	architecture	failure	difficulty	testcase	blockedby	blocking	related
4091	Parse error on curried context of instance declaration	basvandijk		"Assume we have the following classes:
{{{
class C1 a; class C2 a; class C3 a; class C4 a
}}}

GHC allows you to write a type with an uncurried context, as in:
{{{
foo :: (C1 a, C2 b, C3 c) => a -> b -> c
}}}
It also allows you to write a type with a curried context, as in:
{{{
foo :: C1 a => C2 b => C3 c => a -> b -> c
}}}
However it is not allowed to use this curried style of contexts in instance declarations, as in:
{{{
instance C1 a => C2 b => C3 c => C4 (SomeType a b c) 
}}}
Is this intentional?"	feature request	new	normal	_|_	Compiler	6.12.2				Unknown/Multiple	Unknown/Multiple	None/Unknown