Independent of my previous call for discussion about ZCML conflict resolution, I'm cutting and pasting my side of a discussion about the ZCML "includeOverrides" directive from an IRC chat, because it may come in useful for folks grappling with its behavior. There's not really any human-consumable docs about it.
If I've made any mistakes, please let me know. [13:42] <mcdonc> so ftr, i've found that ZCML's includeOverrides and include to do (at least on one vector) exactly the opposite of what you might expect them to do [13:42] <mcdonc> "includeOverrides" is a poor name [13:42] <mcdonc> what it does is to emulate the behavior of inlining stuff into the file you use it from [13:43] <mcdonc> when you use includeOverrides it's as if you typed all the directives in the included file into the file you're including from [13:43] <mcdonc> otoh, "include" doesnt behave like this [13:44] <mcdonc> you can actually define the same directive in three files [13:44] <mcdonc> configure.zcml, one.zcml, and two.zcml [13:44] <mcdonc> and if you use "include" from configure.zcml of one and two [13:44] <mcdonc> there will be no conflict [13:45] <mcdonc> this is because non-conflicting "rootmost" directives win [13:45] <mcdonc> otoh, if you use includeOverrides of one and two from configure.zcml [13:45] <mcdonc> all three will conflict [13:45] <mcdonc> because its as if you typed them all in configure.zcml by hand [13:45] <mcdonc> and that means there are three conflicting rootmost directives [13:46] <mcdonc> if you mentally substitute "inline" for "includeOverrides" it makes a little more sense [13:48] <mcdonc> override is exactly the wrong phrase to use in the name of this directive [13:51] <mcdonc> what it boils down to is that you never, ever really want to use includeOverrides except in your rootmost zcml file [13:51] <mcdonc> and probably not even there [13:51] <mcdonc> because you can get the same effect by typing the directives there by hand - C _______________________________________________ Zope-Dev maillist - Zope-Dev@zope.org https://mail.zope.org/mailman/listinfo/zope-dev ** No cross posts or HTML encoding! ** (Related lists - https://mail.zope.org/mailman/listinfo/zope-announce https://mail.zope.org/mailman/listinfo/zope )
