The function library in Jex Basic is empty. Only one predicate is allowed per step. Only the following operators are supported "=". Use of parenthesis is not supported. Namespaces are not supported. Only the child axis is supported. The concept of variables is not used in Jex.

The function library in Jex Basic includes only the "contains()" and "not()" function. Only one predicate is allowed per step. Only the following operators are supported "=", "!=", "<", ">", "<=", ">=", "or", "and". Namespaces are not supported. Only the child axis is supported. The concept of variables is not used in Jex. When using comparison operators "=", "!=", "<", ">", ">=" or "<=" both sides result in a single scalar value: string, number, or true, false or null. If this is not the case the expression has the value false. E.g., if multiple attributes or a multivalued attribute or an MOI is selected by the left side the result will be false.

A Jex conditions expression is equal to the predicate in Jex advanced. Therefore the statements made for the predicate in Jex advanced apply here.