For example, I want to parse the following text: <input type=hidden value=1> I have defined 2 rules match the "type" field and the "value" field, but the sequence of 2 rules is uncertain, that means "<input value=1 type=hidden>" is also legal,so I can't define the rules just like: rule_type >> !space_p >> rule_value The following works at this simple condition: ( (rule_type >> !space_p >> rule_value) | (rule_value >> !space_p

...

rule_type ) )

But if there are many out-of-order fields need to parser, how can I ignore the sequence of the rules? Thanks, moosefly