Background. For purpose of discussion, let A and B be tags, and let the goal be to convert B to A. There are two independent methods for doing this:
- (Looking forward): Creating a tag synonym A $\leftarrow $B ensures that in the future, any time that tag B is entered, it is silently converted to tag A.
- (Looking back): Merging tag B into tag A ensures that after the moment of merging, no more B tags exist, all having been converted to tag A.
- Synonyms are not linked to 'interesting'/'uninteresting' filters, so a filter for B will not return questions labelled A after the above synonym is created
- Synonyms are community-created: anyone with 1000+ rep can propose a synonym and if it gets 4+ votes it is automatically approved. Conversely, -2 votes automatically kill it.
- Merging does not preclude new instances of B from appearing.
- Merging is irrevocable: synonyms are not.
Discussion Ideally, synonyms do not require any moderator intervention. However, in our current state we don't have enough high rep users who participate at a meta level to create synonyms, and we haven't had any serious tag wars yet. However, we do want to clean up tags, just to make things a little more organized for searching/filtering.
while I can imagine situations where a merge of B to A need not be followed by creating the synonym A $\leftarrow$ B (B is a spam tag and we don't want to clutter the tag synonym list), I suspect that for a while, we will want to do both merging and synonyms together.
Proposed policy: merge+synonym
- Someone creates a RETAG request
- If a request gets at least T votes, then someone should flag the post for moderator attention and a moderator can create the synonym AND merge prior tags.
And T = 4.
We can revisit this later on if needed.