Use const when possible (#63)

src/UnweightedSamplingMulti.jl

@@ -1,47 +1,47 @@
 
 mutable struct SampleMultiAlgR{T,R} <: AbstractWorReservoirSampleMulti
     seen_k::Int
-    rng::R
-    value::Vector{T}
+    const rng::R
+    const value::Vector{T}
 end
 
 mutable struct SampleMultiOrdAlgR{T,R} <: AbstractOrdWorReservoirSampleMulti
     seen_k::Int
-    rng::R
-    value::Vector{T}
-    ord::Vector{Int}
+    const rng::R
+    const value::Vector{T}
+    const ord::Vector{Int}
 end
 
 mutable struct SampleMultiAlgL{T,R} <: AbstractWorReservoirSampleMulti
     state::Float64
     skip_k::Int
     seen_k::Int
-    rng::R
-    value::Vector{T}
+    const rng::R
+    const value::Vector{T}
 end
 
 mutable struct SampleMultiOrdAlgL{T,R} <: AbstractOrdWorReservoirSampleMulti
     state::Float64
     skip_k::Int
     seen_k::Int
-    rng::R
-    value::Vector{T}
-    ord::Vector{Int}
+    const rng::R
+    const value::Vector{T}
+    const ord::Vector{Int}
 end
 
 mutable struct SampleMultiAlgRSWRSKIP{T,R} <: AbstractWrReservoirSampleMulti
     skip_k::Int
     seen_k::Int
-    rng::R
-    value::Vector{T}
+    const rng::R
+    const value::Vector{T}
 end
 
 mutable struct SampleMultiOrdAlgRSWRSKIP{T,R} <: AbstractOrdWrReservoirSampleMulti
     skip_k::Int
     seen_k::Int
-    rng::R
-    value::Vector{T}
-    ord::Vector{Int}
+    const rng::R
+    const value::Vector{T}
+    const ord::Vector{Int}
 end
 
 function ReservoirSample(T, n::Integer, method::ReservoirAlgorithm=algL; ordered = false)
@@ -109,7 +109,10 @@ end
         @inbounds s.value[s.seen_k] = el
         if s.seen_k == n
             recompute_skip!(s, n)
-            s.value = sample(s.rng, s.value, n, ordered=is_ordered(s))
+            new_values = sample(s.rng, s.value, n, ordered=is_ordered(s))
+            @inbounds for i in 1:n
+                s.value[i] = new_values[i]
+            end
         end
     elseif s.skip_k < 0
         p = 1/s.seen_k

src/UnweightedSamplingSingle.jl

@@ -2,14 +2,14 @@
 mutable struct SampleSingleAlgL{T,R} <: AbstractReservoirSample
     state::Float64
     skip_k::Int
-    rng::R
+    const rng::R
     value::T
     SampleSingleAlgL{T,R}(state, skip_k, rng) where {T,R} = new{T,R}(state, skip_k, rng)
 end
 
 mutable struct SampleSingleAlgR{T,R} <: AbstractReservoirSample
     state::Int
-    rng::R
+    const rng::R
     value::T
     SampleSingleAlgR{T,R}(state, rng) where {T,R} = new{T,R}(state, rng)
 end
@@ -54,7 +54,6 @@ end
 function itsample(iter, method::ReservoirAlgorithm = algL)
     return itsample(Random.default_rng(), iter, method)
 end
-
 function itsample(rng::AbstractRNG, iter, method::ReservoirAlgorithm = algL)
     if Base.IteratorSize(iter) isa Base.SizeUnknown
         return reservoir_sample(rng, iter, method)

src/WeightedSamplingMulti.jl

@@ -2,36 +2,36 @@
 mutable struct SampleMultiAlgARes{BH,R} <: AbstractWeightedWorReservoirSampleMulti
     seen_k::Int
     n::Int
-    rng::R
-    value::BH
+    const rng::R
+    const value::BH
 end
 
 mutable struct SampleMultiAlgAExpJ{BH,R} <: AbstractWeightedWorReservoirSampleMulti
     state::Float64
     min_priority::Float64
     seen_k::Int
-    n::Int
-    rng::R
-    value::BH
+    const n::Int
+    const rng::R
+    const value::BH
 end
 
 mutable struct SampleMultiAlgWRSWRSKIP{T,R} <: AbstractWeightedWrReservoirSampleMulti
     state::Float64
     skip_w::Float64
     seen_k::Int
-    rng::R
-    weights::Vector{Float64}
-    value::Vector{T}
+    const rng::R
+    const weights::Vector{Float64}
+    const value::Vector{T}
 end
 
 mutable struct SampleMultiOrdAlgWRSWRSKIP{T,R} <: AbstractWeightedWrReservoirSampleMulti
     state::Float64
     skip_w::Float64
     seen_k::Int
-    rng::R
-    weights::Vector{Float64}
-    value::Vector{T}
-    ord::Vector{Int}
+    const rng::R
+    const weights::Vector{Float64}
+    const value::Vector{T}
+    const ord::Vector{Int}
 end
 
 function ReservoirSample(rng::AbstractRNG, T, n::Integer, method::AlgAExpJ; ordered = false)
@@ -102,7 +102,10 @@ end
         @inbounds s.value[s.seen_k] = el
         @inbounds s.weights[s.seen_k] = w
         if s.seen_k == n
-            s.value = sample(s.rng, s.value, weights(s.weights), n; ordered = is_ordered(s))
+            new_values = sample(s.rng, s.value, weights(s.weights), n; ordered = is_ordered(s))
+            @inbounds for i in 1:n
+                s.value[i] = new_values[i]
+            end
             @inline recompute_skip!(s, n)
             empty!(s.weights)
         end

src/WeightedSamplingSingle.jl

@@ -2,7 +2,7 @@
 mutable struct SampleSingleAlgAExpJ{T,R} <: AbstractReservoirSample
     state::Float64
     skip_w::Float64
-    rng::R
+    const rng::R
     value::T
     SampleSingleAlgAExpJ{T,R}(state, skip_w, rng) where {T,R} = new{T,R}(state, skip_w, rng)
 end