Create an empty heap. compck/heap/comp: forall<a> (pairing-heap<a>) -> ((a, a) -> order) determines the order of elements in the heap.

Remove the minimum element from a heap. Do nothing if the given heap is empty.

Add a value to a heap.

Check whether a heap is empty.

Combine two heaps. Assume they use the same ordering function.

Return the minimum element of a heap.

Create a heap with a single element. compck/heap/comp: forall<a> (pairing-heap<a>) -> ((a, a) -> order) determines the order of elements in the heap.