12 ms·

> Branches are pointers to a commit and that pointer is refreshed when a new commit is created. One could say they are a wandering tag (without explaining a tag

by cesarb 3y ago

> Branches are pointers to a commit and that pointer is refreshed when a new commit is created. One could say they are a wandering tag (without explaining a tag for now). A good name for these "wandering tags" would be "heads", since it's what git calls them internally (for instance, when not packed, they're stored at the "refs/heads/" path in the repository). This also exposes a distinction between a "branch" and its "head", and that distinction can be useful.

lisper 3y ago
Just to make this explicit: a branch in the chain of commits. The start of the chain is pointed to by a head. When you create a new commit on a branch, the head (of that branch) changes to point to the new commit.
- lisper 3y ago
  Arrggh. A branch IS a chain of commits.
galaxyLogic 3y ago
So would it be correct to say that 'heads' are the LEAVES of the commits-tree? Or are there such leaves which are not considered 'heads'?
- Lornedon 3y ago
  No. There are leaves that aren't heads (for example, after you delete a branch, the old commits just lie around until someone deliberately cleans them up), and there are heads that arent' leaves (for example if you branch a new feature branch from main. The feature branch brances off of main, so main is not a leaf anymore)
  - galaxyLogic 3y ago
    > The feature branch brances off of main, so main is not a leaf anymore) But "main" remains a "head" even though the feature branch "continues the graph" from it? So there must be a difference between "Adding a new commit" and "Branching a new commit". I think I got it now. Thanks
    - dasil003 3y ago
      There’s no “branching a new commit” (except as syntactic sugar). Creating a branch creates a new head pointing to an arbitrary commit (even one that already has one or more heads). Committing creates a new commit and moves exactly one head forward to it.

by cesarb 3y ago

lisper 3y ago

Just to make this explicit: a branch in the chain of commits. The start of the chain is pointed to by a head. When you create a new commit on a branch, the head (of that branch) changes to point to the new commit.

lisper 3y ago
Arrggh. A branch IS a chain of commits.

galaxyLogic 3y ago

So would it be correct to say that 'heads' are the LEAVES of the commits-tree? Or are there such leaves which are not considered 'heads'?

Lornedon 3y ago
No. There are leaves that aren't heads (for example, after you delete a branch, the old commits just lie around until someone deliberately cleans them up), and there are heads that arent' leaves (for example if you branch a new feature branch from main. The feature branch brances off of main, so main is not a leaf anymore)
- galaxyLogic 3y ago
  > The feature branch brances off of main, so main is not a leaf anymore) But "main" remains a "head" even though the feature branch "continues the graph" from it? So there must be a difference between "Adding a new commit" and "Branching a new commit". I think I got it now. Thanks
  - dasil003 3y ago
    There’s no “branching a new commit” (except as syntactic sugar). Creating a branch creates a new head pointing to an arbitrary commit (even one that already has one or more heads). Committing creates a new commit and moves exactly one head forward to it.