Add remove_both function.

R/remove-both.R

@@ -0,0 +1,17 @@
+#' Remove both elements of a pair from a list
+#'
+#' @param X A list
+#' @param p A pair
+#'
+#' @return The list X with both elements of p removed (if they exist).
+remove_both <- function(X, p) {
+  m1 <- match(p[1], X)
+  if(!is.na(m1)) {
+    X <- X[-m1]
+  }
+  m2 <- match(p[2], X)
+  if(!is.na(m2)) {
+    X <- X[-m2]
+  }
+  return(X)
+}