It's really about the $error accessor. This, for instance, also fails:

Well, yes and no. Here's a failure without explicitly using $error:

<hansl>

open denmark
loop i = $tmax..($tmax + 1)
    catch value = LRM[i]
    print value
endloop
</hansl>

When the "print" line isn't included, the loop runs fine. (Meaning gretl doesn't complain; but since the 'value' object cannot be used, the whole thing becomes superfluous, so in that sense it's not "fine" at all.)

cheers

sven