[.teal_data S3 method

DESCRIPTION

@@ -73,6 +73,7 @@ Collate:
     'teal.data.R'
     'teal_data-class.R'
     'teal_data-datanames.R'
+    'teal_data-extract.R'
     'teal_data-get_code.R'
     'teal_data-show.R'
     'teal_data.R'

NAMESPACE

@@ -1,6 +1,7 @@
 # Generated by roxygen2: do not edit by hand
 
 S3method("[",join_keys)
+S3method("[",teal_data)
 S3method("[<-",join_keys)
 S3method("[[<-",join_keys)
 S3method("join_keys<-",join_keys)

R/teal_data-extract.R

@@ -0,0 +1,38 @@
+#'
+#' @section Subsetting:
+#' `x[names]` subsets objects in `teal_data` environment and limit the code to the necessary needed to build limited
+#' objects.
+#'
+#' @param names (`character`) names of objects included in `teal_subset` to subset
+#' @param x (`teal_data`)
+#'
+#' @examples
+#'
+#' # Subsetting
+#' data <- teal_data()
+#' data <- eval_code(data, "a <- 1;b<-2")
+#' data["a"]
+#' data[c("a", "b")]
+#'
+#' join_keys(data) <- join_keys(join_key("a", "b", "x"))
+#' join_keys(data["a"]) # should show empty keys
+#' join_keys(data["b"])
+#' join_keys(data)["a"] # should show empty keys
+#' join_keys(data)["b"]
+#'
+#' @rdname teal_data
+#'
+#' @export
+`[.teal_data` <- function(x, names) {
+  checkmate::assert_class(names, "character")
+  names_in_env <- intersect(names, ls(get_env(x)))
+  if (!length(names_in_env)) {
+    return(teal_data())
+  }
+
+  subset_qenv <- getFromNamespace("[.qenv", "teal.code")
+  x <- subset_qenv(x, names_in_env)
+  x@join_keys <- x@join_keys[names_in_env]
+
+  x
+}