feat: add .compile argument to crate function

NEWS.md

@@ -1,5 +1,7 @@
 # mlr3misc 0.13.0-9000
 
+* Added argument `.compile` to function `crate()` because R disables byte-code
+compilation of functions when changing their enclosing environment
 * Added the possibility to include prototype arguments when adding elements to a `Dictionary`
 * Removed unused argument `required_args` from `Dictionary` class
 * Disable leanification when `ROXYGEN_PKG` environment variable is set

R/crate.R

@@ -9,6 +9,10 @@
 #'   The objects, which should be visible inside `.fn`.
 #' @param .parent (`environment`)\cr
 #'   Parent environment to look up names. Default to [topenv()].
+#' @param .compile (`logical(1)`)\cr
+#'   Whether to jit-compile the function.
+#'   In case the function is already compiled.
+#'   If the input function `.fn` is compiled, this has no effect, and the output function will always be compiled.
 #'
 #' @export
 #' @examples
@@ -24,8 +28,20 @@
 #' z = 300
 #' f = meta_f(1)
 #' f()
-crate = function(.fn, ..., .parent = topenv()) {
+crate = function(.fn, ..., .parent = topenv(), .compile = TRUE) {
+  assert_flag(.compile)
+  .compile = .compile || is_compiled(.fn)
   nn = map_chr(substitute(list(...)), as.character)[-1L]
   environment(.fn) = list2env(setNames(list(...), nn), parent = .parent)
-  .fn
+  if (.compile) {
+    .fn = compiler::cmpfun(.fn)
+  }
+  return(.fn)
+}
+
+is_compiled = function(x) {
+  tryCatch({
+    capture.output(compiler::disassemble(x))
+    TRUE
+  }, error = function(e) FALSE)
 }

tests/testthat/test_crate.R

@@ -12,3 +12,9 @@ test_that("crate", {
   f = meta_f(1)
   expect_equal(f(), c(1, 200, 300))
 })
+
+test_that("compilation works", {
+  expect_false(is_compiled(crate(function() NULL, .compile = FALSE)))
+  expect_true(is_compiled(crate(function() NULL, .compile = TRUE)))
+  expect_true(is_compiled(crate(compiler::cmpfun(function() NULL), .compile = FALSE)))
+})