Running examples in 'smoof-Ex.R' failed
The error most likely occurred in:

> ### Name: autoplot.smoof_function
> ### Title: Generate ggplot2 object.
> ### Aliases: autoplot.smoof_function
> 
> ### ** Examples
> 
> library(ggplot2)
> 
> # Simple 2D contour plot with activated heatmap for the Himmelblau function
> fn = makeHimmelblauFunction()
> print(autoplot(fn))
> print(autoplot(fn, render.levels = TRUE, render.contours = FALSE))
> print(autoplot(fn, show.optimum = TRUE))
> 
> # Now we create 4D function with a mixed decision space (two numeric, one discrete,
> # and one logical parameter)
> fn.mixed = makeSingleObjectiveFunction(
+   name = "4d SOO function",
+   fn = function(x) {
+     if (x$disc1 == "a") {
+       (x$x1^2 + x$x2^2) + 10 * as.numeric(x$logic)
+     } else {
+       x$x1 + x$x2 - 10 * as.numeric(x$logic)
+     }
+   },
+   has.simple.signature = FALSE,
+   par.set = makeParamSet(
+     makeNumericParam("x1", lower = -5, upper = 5),
+     makeNumericParam("x2", lower = -3, upper = 3),
+     makeDiscreteParam("disc1", values = c("a", "b")),
+     makeLogicalParam("logic")
+   )
+ )
> pl = autoplot(fn.mixed)
> print(pl)
Error in namespaceExport(ns, exports) : 
  undefined exports: %s!=%, %s!==%, %s+%, %s<%, %s<=%, %s==%, %s===%, %s>%, %s>=%, %stri!=%, %stri!==%, %stri+%, %stri<%, %stri<=%, %stri==%, %stri===%, %stri>%, %stri>=%, stri_datetime_add<-, stri_sub<-, stri_subset<-, stri_subset_charclass<-, stri_subset_coll<-, stri_subset_fixed<-, stri_subset_regex<-, stri_c, stri_c_list, stri_cmp, stri_cmp_eq, stri_cmp_equiv, stri_cmp_ge, stri_cmp_gt, stri_cmp_le, stri_cmp_lt, stri_cmp_neq, stri_cmp_nequiv, stri_compare, stri_conv, stri_count, stri_count_boundaries, stri_count_charclass, stri_count_coll, stri_count_fixed, stri_count_regex, stri_count_words, stri_datetime_add, stri_datetime_create, stri_datetime_fields, stri_datetime_format, stri_datetime_fstr, stri_datetime_now, stri_datetime_parse, stri_datetime_symbols, stri_detect, stri_detect_charclass, stri_detect_coll, stri_detect_fixed, stri_detect_regex, stri_dup, stri_duplicated, stri_duplicated_any, stri_enc_detect, stri_enc_detect2, stri_enc_fromutf32, stri_enc_get, stri_enc_inf
Calls: print ... tryCatch -> tryCatchList -> tryCatchOne -> <Anonymous>
Execution halted