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From: keithd@cadovax.UUCP (Keith Doyle)
Newsgroups: net.micro.amiga,net.lang.forth
Subject: Re: Need help with MVP-Forth
Message-ID: <1016@cadovax.UUCP>
Date: Mon, 3-Mar-86 18:52:06 EST
Article-I.D.: cadovax.1016
Posted: Mon Mar  3 18:52:06 1986
Date-Received: Thu, 6-Mar-86 03:09:10 EST
References: <1360@tekgvs.UUCP>
Reply-To: keithd@cadovax.UUCP (Keith Doyle)
Distribution: na
Organization: CONTEL CADO Systems, Torrance, CA
Lines: 53
Xref: dcdwest net.micro.amiga:2225 net.lang.forth:326

In article <1360@tekgvs.UUCP> keithe@tekgvs.UUCP (Keith Ericson) writes:
>How does one specify the screen-file for MVP-FORTH to use?
>keith

Rather than manually decompile MVP-Forth, check the screen file
mvpamiga.scr.  This is apparently the entire source for MVP-Forth,
in a cross compiler format that looks an awful lot like the 'Nautilus'
cross compiler.  This is how I found out how that stuff works, the
words FROM and INCLUDE are commented on their source screens.
 
Use the word FROM, followed by the file name.  For example:

FROM MVPUTILS.SCR

will select the file mvputils.scr for its screen file.  I stumbled around
awhile for this one too.  I kept expecting it to automatically append
.SCR on to the end of the filenames like LMI Forth's USING word does.

You can also use   INCLUDE MVPUTILS.SCR  which
does effectively:

FROM MVPUTILS.SCR
1 LOAD
CLOSEFILE   ( or whatever the close word is, I forget)

Also note, that if you do a VLIST to list the dictionary, it seems as if
you can't interrupt it.  Actually, you can.  You have to hit the space bar
3 times in fairly quick succesion to do an interrupt.  I found this while
perusing the supplied source, and found that they like to use the 'PAUSE'
word to check for pause or interrupts.  PAUSE will check if there is a key
and if none, will exit PAUSE.  If there is a keystroke, PAUSE will discard it
and wait for another.  After a second keystroke, it will discard that and
wait a short delay time for a third.  If PAUSE gets a third key, it will
do a QUIT (or maybe ABORT) to bail out, otherwise do a normal exit from
PAUSE.  Kind of a lame scheme.  I would have had PAUSE check the keystrokes
for an ESC or CTL-C to exit, a bit cleaner.  Fortunately it can be changed
without too much trouble.

Anyone notice how SLOW it is when you do VLIST?   Yet the screen editor
'laxen.ed' is pretty fast.  I've had problems on other screen editors on
other Forths in keeping up but found this one pretty reasonable considering
it is continually outputting the cursor row and column (the first 'feature'
I removed by the way).  Makes me wonder what gives with VLIST.  Haven't
had the time to check.

There dosen't seem to be an interrupt out of an endless loop that I've
been able to discover.  If anyone knows of one (and/or perhaps good reasons
why it was difficult) please post.

Keith Doyle
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