Sum with multivalue token

[Shaft]

How to sum the values of a multivalue token in Simple XML?

Let's say you have a mv token named test1 with values of: 1,2,3

How to achieve something like:
<eval token="test2">sum($test1$)</eval>

Thanks!

[Shaft]

What a trick! Well done....

[ITWhisperer · Accepted solution]

One way might be to use relative_time which will interpret strings

<eval token="test2">if(mvcount($test1$)>1,relative_time(0,"@s+".mvjoin($test1$,"s+")."s"),$test1$)</eval>

Be aware that is $test1$ is from something like a multiselect dropdown, you may need to use $form.test1$ to get the multivalue version of the field rather than the concatenated version.