[daveplummermd]

Folks, could anyone provide an example of how to use "removeAllBy". There is no such example in the programs provided under examples and I don't understand the arguments that need to be included.

Thanks in advance
Dave Plummer MD

[Gukalov]

Code: Select all

implement main
    open core
 
clauses
    run() :-
        X = "abc",
        List = [ "ABC", "aBc", "cba", "abc", "AbC", "abC" ],
        L = list::removeAllBy(string::compareIgnoreCase, List, X),
%        L = list::removeAllEq({(A, B) :- equal = string::compareIgnoreCase(A,B)}, List, X),
%        L = list::filter(List, {(A) :- equal <> string::compareIgnoreCase(A,X)}),
        console::write(L),
        _ = console::readLine().
 
end implement main
 
goal
    console::runUtf8(main::run).

[daveplummermd]

Thank you for the example.
There is some stuff here I don't understand but I'll work through it using debug to learn.
Again, thanks for your reply.

[daveplummermd]

Gukalov

is it possible to do this same thing with different domains?
For example if x=1 and List=[1,2,3] in your example? What is the comparator to be used?

Code: Select all

X=1, 
List=[1,2,3],
L = list::removeAllBy(somecomparitor, List, X),

dave

[Gukalov]

Code: Select all

class predicates
    somecomparItor : core::comparator{PofigChyo}. % define your own domain here instead of "PofigChyo"
clauses
    somecomparItor(A, B) = less :- A < B, !. % define your own "less" here instead of "A < B,".
    somecomparItor(A, B) = greater :- A > B, !. % define your own "greater" here instead of "A > B,".
    somecomparItor(_, _) = equal.

I think that using list::removeAllBy is not the best way to clean the lists.

[Thomas Linder Puls]

The predicate removeAllBy is used when you want to supply your own comparison routine.

For strings it could for example (as above) be a comparison that consider uppercase and lowercase letters the same.

But for numbers it would (almost always) be natural to use the normal number comparison.

Code: Select all

clauses
    run() :-
        L1 = [1, 2, 3, 4, 5],
        L2 = list::removeAllBy(compare, L1, 4),
        stdio::writef("L2 = %\n", L2).

However, that is exactly what the predicate removeAll does:

Code: Select all

clauses
    run() :-
        L1 = [1, 2, 3, 4, 5],
        L2 = list::removeAll(L1, 4),
        stdio::writef("L2 = %\n", L2).