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Changes between Version 9 and Version 10 of ScopedTypeVariables

v9	v10
41	41	cmp x y = compare (f x) (f y)
42	42	}}}
43		In the latter two cases, the variable can stand for any type, not necessarily a type variable is in these examples, i.e. the variable is existentially quantified.
	43	In the latter two cases, the variable can stand for any type, not necessarily a type variable as in these examples, i.e. the variable is existentially quantified.
44	44	Hugs supports only pattern type signatures, with the type variables universally quantified.
45	45
…	…
69	69	is allowed.
70	70
71		* A rule like ExplicitQuantification would most likely be needed if these were put into the standard.
	71	* With pattern and result signatures, one must examine outer bindings to determine whether an occurrence of a type variable is a binding.
	72	This creates a potential trap.
	73	A rule like ExplicitQuantification might be needed if these were put into the standard.
72	74
73	75	== Proposal 1 ==
…	…
88	90	(perhaps this text can be cleaned up further? what is a better term for expression type signature?)
89	91
	92	== Proposal 2 ==
	93
	94	Restrict the above extensions to:
	95	* for function bindings, optional explicit `forall`s in type signatures.
	96	* for pattern bindings, result type signatures.
	97	Explicit universal quantification might be made mandatory.
	98	plus binding of type variables in instance heads.