call_mirai retrieves the value of a mirai, waiting for the the
asynchronous operation to resolve if it is still in progress.
call_mirai_ is a variant that allows user interrupts, suitable for
interactive use.
call_mirai(aio)
call_mirai_(aio)a 'mirai' object.
The passed mirai (invisibly). The retrieved value is stored at
$data.
This function will wait for the async operation to complete if still in progress (blocking).
The mirai updates itself in place, so to access the value of a mirai
x directly, use call_mirai(x)$data.
The value of a mirai may be accessed at any time at $data, and
if yet to resolve, an 'unresolved' logical NA will be returned instead.
Using unresolved on a mirai returns TRUE only if a mirai
has yet to resolve and FALSE otherwise. This is suitable for use in
control flow statements such as while or if.
If an error occurs in evaluation, the error message is returned as a
character string of class 'miraiError' and 'errorValue' (the stack trace
is available at $stack.trace on the error object).
is_mirai_error may be used to test for this.
is_error_value tests for all error conditions including
'mirai' errors, interrupts, and timeouts.
if (interactive()) {
# Only run examples in interactive R sessions
# using call_mirai()
df1 <- data.frame(a = 1, b = 2)
df2 <- data.frame(a = 3, b = 1)
m <- mirai(as.matrix(rbind(df1, df2)), .args = list(df1, df2), .timeout = 1000)
call_mirai(m)$data
# using unresolved()
m <- mirai({
res <- rnorm(n)
res / rev(res)
},
n = 1e6)
while (unresolved(m)) {
cat("unresolved\n")
Sys.sleep(0.1)
}
str(m$data)
}