how to compare strings in prolog

Question

I want to write a program in prolog that compares two strings or string lists. I want achieve the following:

if StringList A == StringList B
   {
     do this
   }
else
   do something else

How can I achieve this?

Please search before asking. First link in google is http://stackoverflow.com/questions/3647506/code-to-compare-two-strings-in-prolog — ДМИТРИЙ МАЛИКОВ, Oct 30 '12 at 20:54
A string might be several things in Prolog, [see this answer](http://stackoverflow.com/a/8269897/772868) — false, Oct 30 '12 at 21:08

score 2 · Answer 1 · answered Oct 30 '12 at 20:50

2

What do you mean by do this? It hard to implement doing somewhat in Prolog, because all that you've got is facts and predicates.

?- (string1 = string2, X=1); (string1 \= string2, X=2).
X = 2.

answered Oct 30 '12 at 20:50

ДМИТРИЙ МАЛИКОВ

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Soory I did not explain properly. I need to write a program in prolog like this; If (stinglistA == 'C', 'a', 'n','c', 'e','l') { M1= 'C' and M2 ='a') else M1 = M1 and M2 = m2 – Jro Oct 31 '12 at 20:02

score 1 · Answer 2 · edited Oct 30 '12 at 21:06

1

Here's how you'd do it in a single line:

...
(A = B -> do this ; do something else)
...

edited Oct 30 '12 at 21:06

Chris Gerken

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answered Oct 30 '12 at 20:47

CapelliC

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score -1 · Answer 3 · answered Aug 04 '19 at 09:16

 /*SWI prolog code*/
string1(progga).
string2(ikra).

go:-
write("Enter your name"),
nl,
read(X),nl,
string1(Y),
X=@=Y,nl, write("Matched");
write("not Matched"),go2.

/*Another way to*/
go2:-                
string1(A),
string2(B),
A=@=B,nl, write("Matched");
write("not Matched").

how to compare strings in prolog

3 Answers3