SdFiler error Hp50G

[DavidM]

(12-13-2018 07:57 PM)pier4r Wrote:  Impressive knowledge of the system! I wouldn't find such info even after years of intense trial and errors.

The reality is not so impressive, though. I learned this the hard way: one day I noticed that several of my programs were throwing that error right away when I was trying to run them. I knew they had been fine before, and it took me quite a while to narrow down the problem. I had determined that it occurred during NULLLAM allocation, and then did a search on the comp.sys.hp48 newsgroup for "NULLLAM Undefined Local Name". One of the posts found by that search provided the essential clue: I had turned off Last Stack the day before while doing some testing and had forgotten to turn it back on, and that was the cause of the problem. It took me enough time to figure out that I'm not likely to forget it any time soon.

I'm a little surprised that more SysRPL programmers hadn't reported this problem on the comp.sys.hp48 newsgroup, because the Kalinowski/Dominik "Programming in System RPL (Second Edition)" book specifically recommends a method of NULLLAM binding (on page 115) that will trigger this problem. That book is considered by many to be the "SysRPL bible" for the later RPL calculators, so I would have thought this to be a more common issue for SysRPL programmers than it appears to be.