siena::TagSetList Class Reference

interface of a generic predicate in the "tagset" Siena data model. More...

#include <tags.h>

Classes
class	Iterator
	interface of a generic reference to a tagset in a tagset list. More...

Public Member Functions
virtual	~TagSetList ()
	virtual destructor
virtual Iterator *	first () const =0
	returns an iterator over this predicate. More...

Detailed Description

interface of a generic predicate in the "tagset" Siena data model.

A predicate is essentially a collection of tag sets, thus the name TagSetList. Each tag set F in a predicate represents a logical filter that matches a message described by another tagset M when M is a superset of F. Thus a message defined by a tag set M matches a predicate P if and only if P contains at least one tag set F such that M is a superset of F. The tag sets in a predicate can be accessed sequentially through a TagSetList::Iterator.

The following code exemplifies the structure and access mode for a TagSetList:

#include <siena/tags.h>

class SimpleTagSetList : public siena::TagSetList {
    //... 
};

SimpleTagSetList tsl;
// ... here we

//
// we now print the content of tsl
//
siena::TagSetList::Iterator * ts = tsl.first();
if (ts == 0) {
    cout << "no tag sets" endl;
} else {
    cout << "Tag set:";
    siena::TagSet::Iterator * ts->first();
    if (i != 0) {
        do {
            std::cout << " " << i->to_string();
        } while(i->next());
        delete(i);
        cout << std::endl;
    }
    delete(ts);
}

Notice that iterators must be explicitly deallocated.

Examples:

simple_tags_types.h.

Member Function Documentation

virtual Iterator* siena::TagSetList::first ( ) const

pure virtual

returns an iterator over this predicate.

Returns

iterator pointing to the first tag set in this predicate, or 0 (NULL) if this predicate is empty.

Examples:

simple_tags_types.h.