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up arrow vs BST behaviour in PRGM mode.

Posted: Mon Jun 29, 2020 6:27 pm
by EM41
When I was entering a long program I observed the following strange behaviour.

Enter the following program as example

01 LBL ABC
02 *
03 /
04 +
05 -
06 END

Now use the XEQ function to add any command you wish somewhere in between the previous commands like in this case RDN.

01 LBL ABC
02 *
03 /
04 RDN
05 +
06 -
07 END

Go to line 03 with the up arrow and delete it, now both line 03 and 04 are deleted.
This does not happen when you go to line 03 with BST, then only line 03 is deleted.
Entering a direct command from the keyboard such as SIN also doesn't show the "bug"
I only use BST and SST now when I edit but the arrows are more convenient.
You only run into it when you make some mistakes you want to correct.

Erik

Re: up arrow vs BST behaviour in PRGM mode.

Posted: Tue Jun 30, 2020 3:14 am
by rprosperi
Confirmed, and really quite odd too!

Thanks for taking the time to bug it out and document it clearly. I know this kind of bug is not easy to characterize; once you find it and track it down, the write-up looks simple, but I've no doubt it wasn't found after the first time it happened...

Re: up arrow vs BST behaviour in PRGM mode.

Posted: Tue Jun 30, 2020 10:26 pm
by akaTB
Actually you don't need to use any XEQ.
If you enter:

01 LBL ABC
02 *
03 /
04 +
05 -
06 END

and go to line 03 with ▲ followed by <= you end up with:

01 LBL ABC
02 *
03 -
04 END

Re: up arrow vs BST behaviour in PRGM mode.

Posted: Thu Jul 02, 2020 4:18 pm
by EM41
Strange I cannot reproduce the error without inserting a new command.
If I insert a command directly from the keyboard it also doesn't appear in most cases.
Maybe it also depends on what you assign to the arrow keys.

Re: up arrow vs BST behaviour in PRGM mode.

Posted: Thu Jul 02, 2020 6:17 pm
by akaTB
EM41 wrote:
Thu Jul 02, 2020 4:18 pm
Strange I cannot reproduce the error without inserting a new command.
If I insert a command directly from the keyboard it also doesn't appear in most cases.
Maybe it also depends on what you assign to the arrow keys.
Nothing assigned to them.
Via CONF menu: SHIFT+▲ is FAST, SHIFT+▼ is SLOW.

Interestingly both shifted arrows are NULLified after a couple of seconds, unshifted ▼ also responds to NULL, but unshifted ▲ does not.