is.iterator {itertools} | R Documentation |
Utilities for writing iterators
Description
is.iterator
indicates if an object is an iterator.
end_iteration
throws an exception to signal that there
are no more values available in an iterator.
iteration_has_ended
tests an exception to see if it
indicates that iteration has ended.
new_iterator
returns an iterator object.
Usage
is.iterator(x)
end_iteration()
iteration_has_ended(e)
new_iterator(nextElem, ...)
Arguments
x |
any object. |
e |
a condition object. |
nextElem |
a function object that takes no arguments. |
... |
not currently used. |
Examples
# Manually iterate using the iteration_has_ended function to help
it <- iter(1:3)
tryCatch({
stopifnot(is.iterator(it))
repeat {
print(nextElem(it))
}
},
error=function(e) {
if (!iteration_has_ended(e)) {
stop(e)
}
})
[Package itertools version 0.1-3 Index]