'if' in prolog?

Question

Is there a way to do an if in prolog, e.g. if a variable is 0, then to do some actions (write text to the terminal). An else isn\'t even needed, but I can\'t find any docume

Answer 1

You should read Learn Prolog Now! Chapter 10.2 Using Cut. This provides an example:

max(X,Y,Z) :- X =< Y,!, Y = Z.

to be said,

Z is equal to Y IF ! is true (which it always is) AND X is <= Y.