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by davidcuddeback 3121 days ago
I don't understand what point you're trying to make. Unreachable data can be garbage-collected in Haskell, ML, Clojure, Erlang, and many other functional (and non-functional) programming languages. What about GC is supposed to refute that a data structure is functional?
1 comments
Simon_says 3121 days ago
19870213's point was that a git rebase is functional because it doesn't change existing commits, rather it only makes new ones and moves branch pointers. This is correct. You can also say that git gc is functional because it's only garbage collecting. But you can't have it both ways. The cumulative effect of rebase followed by gc is to delete commits that have a branch pointing to them.
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rootlocus 3121 days ago
> The cumulative effect of rebase followed by gc is to delete commits that have a branch pointing to them.

This is both false and irrelevant.

It's false because after the rebase, the branch you just rebased won't point to the old commits. Unless you had other branches there, they would be orphaned. Also, according to the "Notes" section of the git-gc documentation [0]:

> git gc tries very hard not to delete objects that are referenced anywhere in your repository. In particular, it will keep not only objects referenced by your current set of branches and tags, but also objects referenced by the index, remote-tracking branches, refs saved by git filter-branch in refs/original/, or reflogs (which may reference commits in branches that were later amended or rewound).

Since the commit you were on before making the rebase is in the reflog, it will actually not be GCed (yet) even though there are no branches pointing to them.

It's irrelevant because, even if it was true, as long as there are no more objects referencing that commit, it's perfectly eligible for gc. I don't understand your argument that "you can't have it both ways".

[0] https://git-scm.com/docs/git-gc

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davidcuddeback 3121 days ago
> The cumulative effect of rebase followed by gc is to delete commits that have a branch pointing to them.

That would be a strictly broken GC if it removes commits that are reachable from branch pointers. Please file a bug report with the git project if you've observed this happening, because it would be inconsistent with the git-gc(1) manpage, which says it only removes unreachable objects.

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dustingetz 3121 days ago
hey you're getting downvoted bc you misunderstand so insistently and cockily, maybe try asking a question
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