Eeek!GHCi在我的代码中发现了Skolems!
...
Couldn't match type `k0' with `b'
because type variable `b' would escape its scope
This (rigid, skolem) type variable is bound by
the type signature for
groupBy :: Ord b => (a -> b) -> Set a -> Set (b, [a])
The following variables have types that mention k0
...
这些是什么？他们对我的计划有什么要求？为什么他们试图逃脱(忘恩负义的小战士)？