i am implementing logic gates in prolog but having this error

Question

and(A,B) :- A, B.

or(A,_) :- A.
or(_,B) :- B.


error that i am getting is this

compiling C:/Users/firoz/OneDrive/Desktop/neww codes/tt.pl for byte code... C:/Users/firoz/OneDrive/Desktop/neww codes/tt.pl:10: warning: singleton variables [Expr] for do/2 C:/Users/firoz/OneDrive/Desktop/neww codes/tt.pl:11: warning: discontiguous predicate do/3 - clause ignored C:/Users/firoz/OneDrive/Desktop/neww codes/tt.pl compiled, 11 lines read - 2112 bytes written, 7 ms

Did you read the [documentation of GNU prolog](http://www.gprolog.org/manual/html_node/index.html) ? What book did you read about Prolog (in general)? Please notice that **StackOverflow is *not* a do-my-homework website** — Basile Starynkevitch, May 04 '21 at 08:57

score 3 · Answer 1 · answered May 04 '21 at 08:55

3

You are missing a comma in this line:

do(_,_,Expr):- Expr,!,write(true),nl.

answered May 04 '21 at 08:55

jf_

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even after that it is also giving same error – zaman ahmad May 04 '21 at 08:56
Are you sure you are compilng the same program? You error message states errors involving `do/2` and `Expr` in lines 10-11, but they appear in lines 23 onward in your code snippet. – jf_ May 04 '21 at 08:59
yes i am compiling the same code and it shows this – zaman ahmad May 04 '21 at 09:01
1

Both errors go away with this fix. Also in GNU. As you are using Wind-os better restart GNU Prolog. – false May 04 '21 at 09:04
Both errors go away with this fix. Also in GNU. As you are using Wind-os better restart GNU Prolog. – false May 04 '21 at 09:04

i am implementing logic gates in prolog but having this error

1 Answers1