package org.simantics.scl.runtime.equations;

import org.simantics.scl.runtime.SCLContext;
import org.simantics.scl.runtime.function.Function;
import org.simantics.scl.runtime.tuple.Tuple0;

public interface EquationContext {
    void listenEquationVariable(String variableName, Function callback);
    void setEquationVariable(String variableName, Object value);
    
    public static Object applyEquationContext(Function f, EquationContext equationContext) {
        SCLContext context = SCLContext.getCurrent();
        Object oldEquationContext = context.put("equation", equationContext);
        try {
            return f.apply(Tuple0.INSTANCE);
        } finally {
            context.put("equation", oldEquationContext);
        }
    }
}