| 1 |
Thanks a lot for this list! |
| 2 |
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| 3 |
You are totally right, simply translating the dependencies into SAT constraints and feeding them to a solver returns in most cases a very bad, totally useless solution. |
| 4 |
However, nowadays many solvers support solution optimization, i.e., you can specify an ordered list of criteria you want to maximize/minimize, exactly like you did. |
| 5 |
I already implemented the minimal status difference and the minimal installation size criteria, and the solutions I get are already acceptable/good. |
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| 7 |
I wasn't aware of the criteria list you gave (maybe it's in the PMS), so thank you very much, this is a big help :) |
| 8 |
I have few questions about these criteria: |
| 9 |
- in criteria a., there could be an ambiguity between what I call a package (e.g., 'app-editors/nano-2.9.3') and a package group (e.g., 'app-editors/nano'): is the criteria about package group (i.e., are version changes allowed)? |
| 10 |
- similarly in criteria b.: is this criteria valid across versions (i.e., when changing version, the USE-flag change should be minimal), across slots (i.e., two installed versions of the same package group should have a minimal USE flag difference)? |
| 11 |
If yes, what if package.use specifies very different USE flags for two versions of the same package group? |
| 12 |
- does the "prefer new version" criteria go between a. and b.? |
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| 14 |
>> b. Similarly, the number of USE-flag changes necessary to achieve this |
| 15 |
>> aim should be minimized. |
| 16 |
>> (You didn't tell whether your solver already supports such changes, |
| 17 |
>> but when it is finished, it definitely should.) |
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| 19 |
Yes, my solver supports USE-flag, keyword and mask changes (it is currently oblivious of licenses, but supporting them should just be a technical/time consuming effort). |
| 20 |
Due to keywords and mask changes, the "prefer new version" criteria needs to be after criteria "less keyword and mask change". |
| 21 |
- just to be sure, the "less keyword and mask change" criteria is at the top of the list? |
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| 23 |
Best regards, |
| 24 |
Michael Lienhardt |
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