On Wed, Oct 23, 2024 at 7:56 AM Sven Schreiber <sven.schreiber(a)fu-berlin.de&gt; wrote: Condensed version of the failing code posted by Sven: <hansl> function void checklist_bad (const list L, const series b) varlist # what series are defined? list all = L b end function open denmark list outs = IBO IDE checklist_bad(outs, IDE) </hansl> The error message is: "'b': no such object". The call to "varlist" (which I inserted) reveals that the only series "visible" inside checklist() are const and L.IBO -- L.IDE and b (which refer to the same series) have disappeared. This is now fixed in git. The trouble had to do with the treatment of "const" series as function arguments: instead of being copied they just have their "stack_level" (which is 0 at the main level of execution) temporarily incremented so that they're visible inside the function. In this case the stack_level for IDE got incremented twice, once in its role as a list member then again as a "const series" argument. So its level ended up as 2 when it should have been 1. We now take care to prevent such double-incrementing. Allin