BiocNeighours has one BiocView that's classification. Is it used by a k-NN classifier in some other package? It seems like it would be much more flexible than Brian Ripley's knn in class.

You can easily answer this question yourself.

> library(BiocPkgTools)
Loading required package: htmlwidgets
> depdf <- buildPkgDependencyDataFrame(repo=c("BioCsoft", "CRAN"),
                                     dependencies=c("Depends", "Imports"))
> head(depdf)
  Package  dependency edgetype
1      a4      a4Base  Depends
2      a4   a4Preproc  Depends
3      a4   a4Classif  Depends
4      a4      a4Core  Depends
5      a4 a4Reporting  Depends
6  a4Base   a4Preproc  Depends
> deplst <- split(depdf$Package, depdf$dependency)

> deplst$BiocNeighbors
 [1] "batchelor"               
 [2] "bluster"                 
 [3] "CellMixS"                
 [4] "concordexR"              
 [5] "cydar"                   
 [6] "GeDi"                    
 [7] "imcRtools"               
 [8] "lemur"                   
 [9] "miloR"                   
[10] "mumosa"                  
[11] "scater"                  
[12] "scDblFinder"             
[13] "scMerge"                 
[14] "scrapper"                
[15] "SingleR"                 
[16] "SpatialFeatureExperiment"
[17] "SpotSweeper"             
[18] "StabMap"                 
[19] "UCell"