Running examples in ‘fwb-Ex.R’ failed
The error most likely occurred in:

> base::assign(".ptime", proc.time(), pos = "CheckExEnv")
> ### Name: fwb
> ### Title: Fractional Weighted Bootstrap
> ### Aliases: fwb print.fwb
> 
> ### ** Examples
> 
> ## Don't show: 
> if (requireNamespace("survival", quietly = TRUE)) (if (getRversion() >= "3.4") withAutoprint else force)({ # examplesIf
+ ## End(Don't show)
+ # Performing a Weibull analysis of the Bearing Cage
+ # failure data as done in Xu et al. (2020)
+ data("bearingcage")
+ 
+ weibull_est <- function(data, w) {
+   fit <- survival::survreg(survival::Surv(hours, failure) ~ 1,
+                            data = data, weights = w,
+                            dist = "weibull")
+ 
+   c(eta = unname(exp(coef(fit))), beta = 1/fit$scale)
+ }
+ 
+ boot_est <- fwb(bearingcage, statistic = weibull_est,
+                 R = 199, verbose = FALSE)
+ boot_est
+ 
+ #Get standard errors and CIs; uses bias-corrected
+ #percentile CI by default
+ summary(boot_est, ci.type = "bc")
+ 
+ #Plot statistic distributions
+ plot(boot_est, index = "beta", type = "hist")
+ 
+ ## Don't show: 
+ }) # examplesIf
> data("bearingcage")
> weibull_est <- function(data, w) {
+     fit <- survival::survreg(survival::Surv(hours, failure) ~ 1, data = data, weights = w, 
+         dist = "weibull")
+     c(eta = unname(exp(coef(fit))), beta = 1/fit$scale)
+ }
> boot_est <- fwb(bearingcage, statistic = weibull_est, R = 199, verbose = FALSE)
Error in `fwb()`:
! `cluster` must be atomic.
Backtrace:
     ▆
  1. ├─(if (getRversion() >= "3.4") withAutoprint else force)(...)
  2. │ └─base::source(...)
  3. │   ├─base::withVisible(eval(ei, envir))
  4. │   └─base::eval(ei, envir)
  5. │     └─base::eval(ei, envir)
  6. └─fwb::fwb(bearingcage, statistic = weibull_est, R = 199, verbose = FALSE)
  7.   └─chk::chk_atomic(cluster)
  8.     └─chk::abort_chk(x_name, " must be atomic", x = x)
  9.       └─chk::err(..., n = n, tidy = tidy, class = "chk_error", call = call)
 10.         └─rlang::abort(msg, class = class, !!!args[named], call = call)
Execution halted