From 8c0674474e659472e062796f727e98be5909738d Mon Sep 17 00:00:00 2001
From: Benjamin Schwendinger <52290390+ben-schwen@users.noreply.github.com>
Date: Sat, 20 Nov 2021 12:21:57 +0100
Subject: [PATCH] replace looped subsetVector with subsetDT

---
 R/data.table.R | 14 ++------------
 1 file changed, 2 insertions(+), 12 deletions(-)

diff --git a/R/data.table.R b/R/data.table.R
index e020ea3e3..c4fdeb83f 100644
--- a/R/data.table.R
+++ b/R/data.table.R
@@ -1301,18 +1301,8 @@ replace_dot_alias = function(e) {
         #       But rather than that complex logic here at R level to catch that and do a shallow copy for efficiency, just do the check inside CsubsetDT
         #       to see if it passed 1:nrow(x) and then CsubsetDT should do the shallow copy safely and centrally.
         #       That R level branch was taken out in PR #3213
-
-        # TO DO: use CsubsetDT twice here and then remove this entire R level branch
-        for (s in seq_along(icols)) {
-          target = icolsAns[s]
-          source = icols[s]
-          ans[[target]] = .Call(CsubsetVector,i[[source]],ii)  # i.e. i[[source]][ii]
-        }
-        for (s in seq_along(xcols)) {
-          target = xcolsAns[s]
-          source = xcols[s]
-          ans[[target]] = .Call(CsubsetVector,x[[source]],irows)   # i.e. x[[source]][irows], but guaranteed new memory even for singleton logicals from R 3.1.0
-        }
+        ans[icolsAns] = .Call(CsubsetDT, i, ii,    icols)
+        ans[xcolsAns] = .Call(CsubsetDT, x, irows, xcols)
         setattr(ans, "names", ansvars)
         if (haskey(x)) {
           keylen = which.first(!key(x) %chin% ansvars)-1L