[h5md-user] Three-level versioning schemes

[Peter Colberg]

On Tue, Sep 03, 2013 at 10:05:15AM +0200, Felix Höfling wrote:
> I understand that the second and third digits are for branches and
> tags, respectively. But what is the first digit for? Minor changes
> increment the tag, and major changes the branch. Will we ever reach
> H5MD 2.x with a three-level scheme?

I revisited the topic of version numbers while preparing releases of
some programs, and now understand the purpose of the major version
number part of a three-level scheme.

Please see H5MD commit ba4d217, which re-introduces a major version
number for both the specification and modules, to allow signaling
backwards-incompatible changes to the file structure.

The specification hopefully remains at major version 1 indefinitely.
For H5MD modules it appears useful to allow rampant breakage [1], but
indicate when doing so by incrementing the major version number.

Peter

[1] Python style… ;-P