http://www.perlmonks.org?node_id=974677


in reply to Per-distro versioning and dependency specification

I always keep the version numbers of modules in my distributions synchronised. While using different version numbers in different modules can be handled sanely, it seems to me there is at least potential for confusion. On the other hand, synchronisation doesn't appear to have many drawbacks. If I bump the version number of one module, then it doesn't seem harmful to bump the version numbers of the rest, even if they haven't seen any other changes.

With regard to changing major version numbers when breaking backwards compatibility, personally I don't think that goes far enough. If I write:

use Foo::Bar 2.00;

... but Foo::Bar 3.00 has a completely changed API, then my code may break in unexpected and confusing ways.

When JSON.pm changed its API between versions 1 and 2, this caused a lot of breakage. The only way to avoid that is to continue to support your old API alongside the new one. In practice this usually means giving your new API a different module name (and perhaps rewriting the old module as a wrapper for the new one).

perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'