not depending on Base.Sort internal values, should work on Julia nightly too

Author: anicusan

README.md

@@ -1,6 +1,6 @@
 # SyncSort: Cross-Architecture Synchronised Sorting of Multiple Arrays
 
-While key-value pairs are standard in sorting, oftentimes these keys and values are kept in separate arrays (see Explanation below); we can sort multiple secondary vector following the values of a primary key vector using a new sorting interface:
+While key-value pairs are standard in sorting, oftentimes these keys and values are kept in separate arrays (see Explanation below); we can sort multiple secondary vectors following the values of a primary key vector using a new sorting interface:
 
 ```julia
 syncsort!(v, rest...)
@@ -11,22 +11,23 @@ ids = rand(Int64, num_particles)
 xcoords = rand(num_particles)
 ycoords = rand(num_particles)
 
+# Reordering applied to `ids` will be done in sync with `xcoords` and `ycoords`
 syncsort!(ids, xcoords, ycoords)
-
 ```
 
 
 ## Explanation
+
 Key-value pair sorting assumes an _Array of Structures_ (AoS) format - e.g., a `Vector{Particle}` where `struct Particle` contains some fields `coord::Float64` and `id::Int64`. However, in many applications, it is more performant to store these fields as a _Structure of Arrays_ (SoA), i.e. separate `coords::Vector{Float64` and `ids::Vector{Int64}`.
 
 If we had an Array of Structures, using standard sorting interfaces - as is the case in virtually all programming languages - we'd do something like:
 
 ```julia
 # One primary key and two secondary values
 struct Particle
-	id::Int64
-	xcoord::Float64
-	ycoord::Float64
+    id::Int64
+    xcoord::Float64
+    ycoord::Float64
 end
 
 # Array of structures
@@ -39,12 +40,12 @@ sort!(particles; by=p->p.id)
 In high-performance applications, we'd use a Structure of Arrays, where we have separate arrays for our keys and values; the typical solution would involve creating a mask of indices sorting the primary array, in Julia named `sortperm`:
 
 ```julia
-# Keys and values held in separate, contiguous arrays - could be bundled in a Structure of Arrays
+# Keys and values held in separate vectors
 ids = rand(Int64, 10_000)
 xcoords = rand(Float64, 10_000)
 ycoords = rand(Float64, 10_000)
 
-# Get indices permutation that sort the primary array
+# Get indices permutation that sorts the primary array
 sorted_indices = sortperm(ids)
 
 # Use indices mask to permute arrays
@@ -53,12 +54,12 @@ xcoords = xcoords[sorted_indices]
 ycoords = ycoords[sorted_indices]
 ```
 
-An easier and much more performant solution - in terms of time, space, and program (re-)design - would be `syncsort`:
+An easier and much more performant solution - in terms of time, space, and especially program (re-)design - would be `syncsort`:
 
 ```julia
 using SyncSort
 
-# Keys and values held in separate, contiguous arrays - could be bundled in a Structure of Arrays
+# Keys and values held in separate vectors
 ids = rand(Int64, 10_000)
 xcoords = rand(Float64, 10_000)
 ycoords = rand(Float64, 10_000)
@@ -69,9 +70,9 @@ syncsort!(ids, xcoords, ycoords)
 
 ## CPU Sorting Credits
 
-The CPU sorting routines in `src/cpu_sort.jl` are copied verbatim from the Julia standard library, with some changes to propagate the secondary arrays and follow the swaps done by the standard sorting routines. All credits go to the Julia contributors, with special thanks to @LilithHafner for writing one of the most performant sorting algorithms of [any programming language](https://github.com/LilithHafner/InterLanguageSortingComparisons) - thank you! The Julia license text is included within the file, while this package is shared under the same MIT license. 
+The CPU sorting routines in `src/cpu_sort.jl` are copied verbatim from the Julia standard library, with some changes to propagate the secondary arrays and follow the swaps done by the standard sorting routines. All credits go to the Julia contributors, with special thanks to @LilithHafner for writing one of the most performant sorting algorithms of [any programming language](https://github.com/LilithHafner/InterLanguageSortingComparisons) - thank you! The Julia license text is included within the file. 
 
 
 ## License
 
-This package is shared under the same license as the Julia standard library, MIT.
+This package is shared under the same license as the Julia standard library, MIT.