Re: Please tell me why this works. I'm pretty sure it shouldn't....

I think you're just lucky in this case. Without knowing exactly which
fields are involved with PMPCNV:*input and RF$PM:*output I can't say for

sure, but I can only think of one way this could work.

When you "EVAL toDS=saveDS", you are essentially treating each DS as a
big character variable. So, if the layout of each matches up to the
length of toDS, you will end up with everything in its right place since

the first %len(toDS) bytes of saveDS will be copied to the memory
starting at %addr(toDS).

If that doesn't make sense I can give an example. Just let me know.

That's what I figured, but I knew that there were fields smack dab in the
middle of the saveDS that weren't in the toDS at all. So after reading
your explanation I thought I should determine which fields exactly were
different. Turns out the only differences were in two date fields that
were being broken down into component parts in the saveDS. That's why
they matched, they were 4,0/2,0 in the saveDS and 6,0 in the toDS.

Like you said. I just got lucky on that one. lol.