Some more restructuring with update! (#52)

src/IteratorSampling.jl

@@ -18,15 +18,20 @@ const ordworsample = OrdWORSample()
 
 abstract type AbstractReservoirSample end
 abstract type AbstractReservoirSampleMulti <: AbstractReservoirSample end
-abstract type AbstractOrdReservoirSampleMulti <: AbstractReservoirSampleMulti end
+abstract type AbstractWorReservoirSampleMulti <: AbstractReservoirSampleMulti end
+abstract type AbstractOrdWorReservoirSampleMulti <: AbstractWorReservoirSampleMulti end
+abstract type AbstractWrReservoirSampleMulti <: AbstractReservoirSampleMulti end
+abstract type AbstractOrdWrReservoirSampleMulti <: AbstractWrReservoirSampleMulti end
 
 struct AlgL end
 struct AlgR end
+struct AlgWRSKIP end
 struct AlgARes end
 struct AlgAExpJ end
 
 const algL = AlgL()
 const algR = AlgR()
+const algWRSKIP = AlgWRSKIP()
 const algARes = AlgARes()
 const algAExpJ = AlgAExpJ()
 

src/SortedSamplingMulti.jl

@@ -43,6 +43,15 @@ function sortedindices_sample(rng, iter, n::Int; replace = false, ordered = fals
     end
 end
 
+function skip_ahead_no_end(iter, state, n)
+    for _ in 1:n
+        it = iterate(iter, state)
+        state = it[2]
+    end
+    it = iterate(iter, state)
+    return it
+end
+
 function get_sorted_indices(rng, n, N, replace)
     if replace == true
         return sortedrandrange(rng, 1:N, n)