try to support older R versions

.travis.yml

@@ -2,7 +2,7 @@
 
 # Setting up R deps
 language: r
-r: 3.2
+r: 3.1
 r_packages: covr
 cache: packages
 

DESCRIPTION

@@ -25,7 +25,7 @@ Description: Functions to simplify the analysis of Antimicrobial Resistance (AMR
     on antibiograms according to Leclercq (2013)
     <doi:10.1111/j.1469-0691.2011.03703.x>.
 Depends:
-    R (>= 3.2.0)
+    R (>= 3.1.0)
 Imports:
     dplyr (>= 0.7.0),
     data.table (>= 1.10.0),

NAMESPACE

@@ -57,6 +57,7 @@ exportMethods(print.tbl)
 exportMethods(print.tbl_df)
 exportMethods(summary.mic)
 exportMethods(summary.rsi)
+importFrom(data.table,data.table)
 importFrom(dplyr,"%>%")
 importFrom(dplyr,all_vars)
 importFrom(dplyr,any_vars)

NEWS.md

@@ -9,6 +9,7 @@
 - New print format for tibbles and data.tables
 
 #### Changed
+- Support for older R versions, only R 3.1.0 and later is needed
 - Renamed dataset `ablist` to `antibiotics`
 - Renamed dataset `bactlist` to `microorganisms`
 - Added more microorganisms to `bactlist`

R/freq.R

@@ -337,7 +337,7 @@ freq <- function(x,
                  '; ',
                  (Count.rest / length(x)) %>% percent(force_zero = TRUE),
                  ')'),
-          '. Use `nmax` to show more rows.\n\n', sep = '')
+          '. Use `nmax` to show more rows.\n', sep = '')
 
     } else {
       print(

R/misc.R

@@ -111,3 +111,12 @@ size_humanreadable <- function(bytes, decimals = 1) {
   out <- paste(sprintf(paste0("%.", decimals, "f"), bytes / (1024 ^ factor)), size[factor + 1])
   out
 }
+
+# strrep is only available in R 3.3 and later
+# and we want to support R 3.2 too, so:
+strrep <- function(x, times) {
+  for (i in 1:length(x)) {
+    x[i] <- paste(rep(x[i], times[i]), collapse = "")
+  }
+  x
+}

R/print.R

@@ -28,6 +28,7 @@
 #' @rdname print
 #' @name print
 #' @importFrom dplyr %>% n_groups group_vars group_size filter pull select
+#' @importFrom data.table data.table
 #' @exportMethod print.tbl_df
 #' @export
 #' @examples