boost multi_index partial indexes
- by Gokul
Hi,
I want to implement inside boost multi-index two sets of keys with same search criteria but different eviction criteria. Say i have two sets of data with same search condition, but one set needs a MRU(Most Recently Used) list of 100 and the other set requires a MRU of 200. Say the entry is like this
class Student
{
int student_no;
char sex;
std::string address;
};
The search criteria is student_no, but for sex='m', we need MRU of 200 and for sex='f', we need a MRU of 100. Now i have a solution where in i introduce a new ordered index to maintain ordering.
For example the IndexSpecifierList will be something like this
typedef multi_index_container<
Student,
indexed_by<
ordered_unique< member<Student, int, &Student::student_no> >,
ordered_unique< composite_key<
member<Student, char, &Student::sex>,
member<Student, int, &Student::sex_specific_student_counter> > >
>
> student_set
Now everytime, i am inserting a new one, i have to take a equal_range for that using index 2 and remove the oldest one and if something is getting re-used, i have to update it by incrementing the counter.
Is there a better solution to this kind of problem?
Thanks,
Gokul.