R/sequential.R
sequential.Rd
A sequential future is a future that is evaluated sequentially in the current R session similarly to how R expressions are evaluated in R. The only difference to R itself is that globals are validated by default just as for all other types of futures in this package.
sequential(..., envir = parent.frame())
Additional arguments passed to Future()
.
The environment from where global objects should be identified.
This function is not meant to be called directly. Instead, the typical usages are:
# Evaluate futures sequentially in the current R process
plan(sequential)
## Use sequential futures
plan(sequential)
## A global variable
a <- 0
## Create a sequential future
f <- future({
b <- 3
c <- 2
a * b * c
})
## Since 'a' is a global variable in future 'f' which
## is eagerly resolved (default), this global has already
## been resolved / incorporated, and any changes to 'a'
## at this point will _not_ affect the value of 'f'.
a <- 7
print(a)
#> [1] 7
v <- value(f)
print(v)
#> [1] 0
stopifnot(v == 0)