@Override public boolean validate(Collection<Variable> variableList) { return VariableUtil.validate(variableList); }
@Override public boolean validate(Variable variable) { return VariableUtil.validate(variable); }
@Override public String toString(Variable variable) { return VariableUtil.toString(variable); }
@Override public String toString(Collection<Variable> variableList) { return VariableUtil.toString(variableList); }
@Override public boolean isEmpty(Variable variable) { return VariableUtil.isEmpty(variable); }