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Es werden Posts vom Oktober, 2009 angezeigt.

On Version Numbers

I have been thinking about using version numbers lately while working on some API extension of the Sling Engine bundle. So here is what I think versions are all about and that we all should be very careful when changing code and assigning versions to it.

On a high level versions have various aspects:
SyntaxThere is no global agreement on the correct syntax of versions. I tend to like the OSGi syntax specification: The version has four parts separated by dots. The first three parts are numbers, called the major, minor and micro version. The fourth part is a plain (reduced character set) string which may be used to describe a particular version. Version numbers are compared as you would expect, except that the fourth part is employs case-sensitive string comparison comparing the actual Unicode codepoints of the characters.SemanticThe semantics of a version define what it means to increment each place of a version. In the world of software development there is even less agreement on the s…