Currently if digraph is immutable:
DigraphRemoveEdges(digraph, [ ]) returns digraph, but
DigraphRemoveEdges(digraph, [[src, ran]]) always returns an immutable copy of digraph even when [src, ran] is invalid, and
DigraphRemoveEdge(digraph, [src, ran]) always returns an immutable copy of digraph even when [src, ran] is invalid
which seems slightly odd, do we want this behaviour?
Currently if
digraphis immutable:DigraphRemoveEdges(digraph, [ ])returnsdigraph, butDigraphRemoveEdges(digraph, [[src, ran]])always returns an immutable copy ofdigrapheven when[src, ran]is invalid, andDigraphRemoveEdge(digraph, [src, ran])always returns an immutable copy ofdigrapheven when[src, ran]is invalidwhich seems slightly odd, do we want this behaviour?