Numeric.VariablePrecision.Precision
	examples of usage in documentation

Numeric.VariablePrecision.Precision.Reify
	examples of usage in documentation

Numeric.VariablePrecision.Float
	readsPrec ignores precedence
	check accuracy of fromRational
	check accuracy of (+), (-), (*)
	check accuracy of (/), recip
	proper (a)(sin|cos|tan)(h) (bad: viaDouble)
	profile and optimise space and time
	consider rounding modes
	consider mixed-precision operations
	consider IEEE -0 semantics

TypeLevel.NaturalNumber.ExtraNumbers
	submit upstream and remove if accepted