[c3] Why Cocoon 3 doesn't use the expression language modules from 2.2

[Reinhard Pötz <re...@apache.org>]

Grzegorz Kossakowski wrote:
> As I was already playing with Cocoon3 I decided to have a closer look
> at source code of it. There are many nice things about it (probably
> the most important one is that this code is much cleaner than what we
> have in c2.2). Nevertheless, what I found surprising is that you
> decided to rewrite EL and OM handling from scratch once again. Was
> there any specific reason for doing that apart from "let's throw out
> the whole c.2.2's core"?

The 2.2 object model is a solution to many problems (e.g. see the
markLocalContext() and cleanupLocalContext() methods, support for
hierarchies, usage together with a jx template) that Cocoon 3.0
doesn't have.
The object model of Cocoon 3 is really focused to provide a read-only
context to expression languages. The object
model + the Jexl language interpreter implementation don't even account
for 50 lines of code. Maybe we could have saved a few lines of them by
using the 2.2 cocoon-expression-language-* modules (+ all the transitive
dependencies) but this seemed to be a rather high price for little outcome.

> I don't recall any discussion about that particular decision.

No there was no common decision. But don't be afraid that C3 is carved
in stone yet. The release that I will propose is tagged with 'alpha' and
this means that we are free to change things whenever we need.

-- 
Reinhard Pötz                           Managing Director, {Indoqa} GmbH
                         http://www.indoqa.com/en/people/reinhard.poetz/

Member of the Apache Software Foundation
Apache Cocoon Committer, PMC member                  reinhard@apache.org
________________________________________________________________________

Re: [c3] Why Cocoon 3 doesn't use the expression language modules from 2.2

[Grzegorz Kossakowski <gr...@tuffmail.com>]

Reinhard Pötz pisze:
> Grzegorz Kossakowski wrote:
>> As I was already playing with Cocoon3 I decided to have a closer look
>> at source code of it. There are many nice things about it (probably
>> the most important one is that this code is much cleaner than what we
>> have in c2.2). Nevertheless, what I found surprising is that you
>> decided to rewrite EL and OM handling from scratch once again. Was
>> there any specific reason for doing that apart from "let's throw out
>> the whole c.2.2's core"?
> 
> The 2.2 object model is a solution to many problems (e.g. see the
> markLocalContext() and cleanupLocalContext() methods, support for
> hierarchies, usage together with a jx template) that Cocoon 3.0
> doesn't have.
> The object model of Cocoon 3 is really focused to provide a read-only
> context to expression languages. The object
> model + the Jexl language interpreter implementation don't even account
> for 50 lines of code. Maybe we could have saved a few lines of them by
> using the 2.2 cocoon-expression-language-* modules (+ all the transitive
> dependencies) but this seemed to be a rather high price for little outcome.

Ok, let's see how this evolves.

>> I don't recall any discussion about that particular decision.
> 
> No there was no common decision. But don't be afraid that C3 is carved
> in stone yet. The release that I will propose is tagged with 'alpha' and
> this means that we are free to change things whenever we need.
> 

Ok.

You skipped my point on missing tags in svn. Do you know why they are missing?

-- 
Grzegorz Kossakowski