What is buildout: zcml?

Question

In one of the buildout.cfg files of my projects, I have something like this:

[buildout]
...
zcml =
    my.package
    plone.reload
...

Everything is working fine, but I'm still puzzled by the reason that some packages need to be listed here, and why there aren't others.

Where to begin?

When doing some research, I end up at https://pypi.python.org/pypi/munin.zope/2.1 , which says that if you use z3c.autoinclude and plone (+3.3), you don’t need it.

Does this mean that if the distribution has z3c.autoinclude slug on its own setup.py, that is

entry_points="""
# -*- Entry points: -*-
[z3c.autoinclude.plugin]
target = plone
""",

you do not need to care about buildout:zcml?

Answer 1

[buildout] , zcml, zcml.

[instance] :

[instance]
recipe = plone.recipe.zope2instance
eggs = Plone
zcml = ${buildout:zcml}

buildout:zcml, buildout:eggs, -, IMO

Answer 2

buildout name=value :

• , .

buildout:zcml .

, buildout:zcml .

, zcml, plone.recipe.zope2instance. .