jny0

I am using swi-prolog, and have two problems:

I need to clear a screen. I have been using the following:

cls:- put(27),put(91),put(56),put(74).

It doesn't seem to work for me, despite being assured that it works.

The second problem I have, is that I need to test for whether a list
is empty. I would like it to work something like this:

is_empty(list) /*succeeds if empty, fails if not*/

Any ideas would be gratefully received.
Cheers
JNY

cesar rabak

JNY escreveu:


This should work only in terminal that are or emulate the ANSI standard.
For a test in the shell try:

$echo -e '\E[2J'

and see if this clears the screen. If yes, then your cls predicate could
work, otherwise, you'll need to find alternatives.

HTH

--
Cesar Rabak
GNU/Linux User 52247.
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paul williams

You're using the sequence ESC [ 8 J, which isn't defined by any standard
I'm aware of. Try changing "56" to "50".

--
Paul

chavez

[] is the empty list.

is_the_empty_list([]).

:- is_the_empty_list([1]).
No.

:- is_the_empty_list([]).
Yes. :- is_the_empty_list(X).
X -> [].
One answer.

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