3 files changed, 6 insertions(+), 2 deletions(-)

M DESCRIPTION
M NEWS
M R/neighbourfun.R

@@ 2,7 2,7 @@ Package: neighbours
 Type: Package
 Title: Neighbourhood Functions for Local-Search Algorithms
 Version: 0.1-0
-Date: 2021-09-01
+Date: 2022-07-04
 Maintainer: Enrico Schumann <es@enricoschumann.net>
 Authors@R: person(given = "Enrico", family = "Schumann",
                   role  = c("aut", "cre"),

@@ 1,4 1,4 @@
-v0.1-0  (2021-??-??)
+v0.1-0  (2022-??-??)
 
   o Initial release.  The package provides a function
     neighbourfun() that constructs neighbourhood

@@ 16,6 16,10 @@ neighbourfun <- function(min = 0,
     budget <- sum
 
     .sub <- function(e, env) {
+        ## replace a subexpression within e by another
+        ## expression, bound in env. Example:
+        ##    .sub(quote(a + b), list(a = function(x) x + 1))
+        ##    ## => function(x) x + 1 + b
         expr <- substitute(substitute(e2, env),
                            env = list(e2 = e))
         eval(expr)