I found a version that works. In the original version I must not have
been using tail recursion correctly. Here is the version that works. Can
anyone explain why the first version doesn't properly trigger tail
recursion?
```
xquery version "3.1";
declare function local:get-random-numbers($how-many as xs:integer,
$generator as map(*), $accumulator) {
if ($how-many ge 1) then
local:get-random-numbers($how-many - 1, $generator?next(),
($accumulator, $generator?number))
else
$accumulator
};
declare function local:get-random-numbers($how-many as xs:integer) {
local:get-random-numbers($how-many, random-number-generator(), ())
};
let $n := 2000
return
local:get-random-numbers($n) => count()
```
On Mon, May 11, 2020 at 5:20 PM Joe Wicentowski <joe...@gmail.com> wrote:
> Hi all,
>
> I encountered a stack overflow error with the following code, which is
> designed to return as many random numbers as the user requests. BaseX's
> error suggested, "Try tail recursion?" I think I am already using tail
> recursion. Changing the $n variable from 1407 to 1406 or lower avoids the
> error. Any number 1407 or higher triggers the error.
>
> Thank you for any hints!
> Joe
>
> ```
> xquery version "3.1";
>
> declare function local:get-random-numbers($how-many as xs:integer,
> $generator as map(*)) {
> if ($how-many ge 1) then
> (
> $generator?number,
> local:get-random-numbers($how-many - 1, $generator?next())
> )
> else
> ()
> };
>
> declare function local:get-random-numbers($how-many as xs:integer) {
> local:get-random-numbers($how-many, random-number-generator())
> };
>
> let $n := 1407
> return
> local:get-random-numbers($n) => count()
> ```
>
