| layout | title | published |
|---|---|---|
default |
nth |
true |
[%CFEngine_function_prototype(list_or_container, position_or_key)%]
Description: Returns the element of list_or_container at zero-based position_or_key.
If an invalid position (above the size of the list minus 1) or missing key is requested, this function does not return a valid value.
[This function can accept many types of data parameters.][Functions#collecting functions]
list_or_container can be an slist or a data container. If it's a
slist, the offset is simply the position in the list. If it's a data
container, the meaning of the position_or_key depends on its
top-level contents: for a list like [1,2,3,4] you will get the list
element at position_or_key. For a key-value map like
{ a: 100, b: 200 }, a position_or_key of a returns 100.
Since 3.15, Nth supports negative indices when indexing lists, starting from
the other end of the list. With a position_or_key of -1, you will get 4
from the list [1,2,3,4].
[%CFEngine_function_attributes(list_or_container, position_or_key)%]
Example:
[%CFEngine_include_snippet(nth.cf, #+begin_src cfengine3, .*end_src)%]
Output:
[%CFEngine_include_snippet(nth.cf, #+begin_src\s+example_output\s*, .*end_src)%]
History: The [collecting function][Functions#collecting functions] behavior was added in 3.9. The ability to use negative indices was added in 3.15.
See also: length(), [about collecting functions][Functions#collecting functions], and data documentation.