ant-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Wolfgang Häfelinger <whaefelin...@epo.org>
Subject Re: Proposed roadmap
Date Wed, 03 Jan 2007 18:50:51 GMT
>> It may be difficult to have an EL in ant as 
>> the components/beans (properties and references) 
>> are not bound by any naming
>> rules [..]

You have a  similar problem in JSP as you are allowed
to define a config parameter named "foo-bar". EL will
treat  ${initParam.foo-bar} as valueof(initParam.foo) 
- valueof(bar) which is not what you want.

However, you can also use ${initParam['foo-bar']} for
names not bound to usual rules.

>> properties and references have different rules (
>> properties are not meant to be overwritten)

EL  does  not  allow you  to override properties (or 
resources).

Btw, it would be rather handy to be able to override
properties. Here Ant could be a bit less dogmatic. Why
not adding an attribute to task property which overrides
if desired??
 
>> and have different namespaces (i.e. one can use the 
>> same name for a property and for a reference).

EL must work on properties, references as well as on any
other data type .., i.e. the EL expression 

${empty varname ? 'empty' : 'not empty'}

must universally work (as it does in JSP).






"Peter Reilly" <peter.kitt.reilly@gmail.com> 
03-01-2007 16:57
Please respond to
"Ant Developers List" <dev@ant.apache.org>


To
"Ant Developers List" <dev@ant.apache.org>
cc

Subject
Re: Proposed roadmap






On 1/3/07, Wolfgang Häfelinger <whaefelinger@epo.org> wrote:
> >> 3. I dont actually like EL handling as the way
> >> any invalid bit the the expression switches the
> >> whole thing to null, instead of telling where
> >> you've left something undefined. That may just
> >> be the JSP2 implementation, of course,.
>
> I like  this actually much more than the Ant way. Too
> many times I created funny directories like ${src.dir}
> et cetera. So I'm not going to miss this Ant "feature".
> It would anyhow only apply for those using EL, for all
> others, the old rule would apply (I assume here that
> you could define on a higher level to use EL or not ..).

It may be difficult to have an EL in ant as the components/beans
(properties and references) are not bound by any naming
rules - so spaces, dots even < and > are allowed:
 <property name="&lt;x&gt;" value="x is this"/>

properties and references have different rules (properties
are not meant to be overwritten) and have different
namespaces (i.e. one can use the same name for a property
and for a reference).

Traditionally in ant one uses nested elements in place of an EL.
  <condition property="trax.impl.present">
      <or>
        <and>
          <isset property="javax.xml.transform.TransformerFactory"/>
          <available classname="${javax.xml.transform.TransformerFactory}"
            classpathref="classpath"/>
        </and>
        <available
resource="META-INF/services/javax.xml.transform.TransformerFactory"/>
      </or>
    </condition>

{from ant's build file}
but this can get a bit verbose.

>
> >> 1. I'm not sure how serious it was
>
> Deadly serious for me ;-) as well as I hope that Peter
> has not been joking with regards to "- add logic/control-
> flow features from jsp/ant-contrib (for, if, while, try,
> var etc)
>
> >> 2. its a traumatic change
>
> Kidding?
>
>
>
>
>
>
> Steve Loughran <stevel@apache.org>
> 03-01-2007 14:58
> Please respond to
> "Ant Developers List" <dev@ant.apache.org>
>
>
> To
> Ant Developers List <dev@ant.apache.org>
> cc
>
> Subject
> Re: Proposed roadmap
>
>
>
>
>
>
> Wolfgang Häfelinger wrote:
> > * 1.9
> >   - add EL (?from jsp/jsf - properties or references?)
> >
> > Since EL is a really cool feature and simplifies JSP development so
> much,
> > I
> > would like to give it a much higher priority (1.7.x)...
> >
>
> 1. I'm not sure how serious it was
> 2. its a traumatic change
> 3. I dont actually like EL handling as the way any invalid bit the the
> expression switches the whole thing to null, instead of telling where
> you've left something undefined. That may just be the JSP2
> implementation, of course,.
>
>
>
>
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: dev-unsubscribe@ant.apache.org
> For additional commands, e-mail: dev-help@ant.apache.org
>
>
>
>

---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@ant.apache.org
For additional commands, e-mail: dev-help@ant.apache.org



Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message