if (FALSE) {
isolate_example("contain side-effects", {
if (requireNamespace("knitr", quietly = TRUE)) {
# First, let's iterate on a drake workflow.
load_mtcars_example()
make(my_plan, history = TRUE, verbose = 0L)
# Naturally, we'll make updates to our targets along the way.
reg2 <- function(d) {
d$x2 <- d$x ^ 3
lm(y ~ x2, data = d)
}
Sys.sleep(0.01)
make(my_plan, history = TRUE, verbose = 0L)
# The history is a data frame about all the recorded runs of your targets.
out <- drake_history(analyze = TRUE)
print(out)
# Let's use the history to recover the oldest version
# of our regression2_small target.
oldest_reg2_small <- max(which(out$target == "regression2_small"))
hash_oldest_reg2_small <- out[oldest_reg2_small, ]$hash
cache <- drake_cache()
cache$get_value(hash_oldest_reg2_small)
# If you run clean(), drake can still find all the targets.
clean(small)
drake_history()
# But if you run clean() with garbage collection,
# older versions of your targets may be gone.
clean(large, garbage_collection = TRUE)
drake_history()
invisible()
}
})
}
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