# \[ANN\] Variables & Conditionals Extension

**URL:** <https://www.ruby-forum.com/t/ann-variables-conditionals-extension/116527>\
**Category:** Radiant CMS\
**Created:** [October 6, 2007, 10:19pm UTC](https://www.ruby-forum.com/t/ann-variables-conditionals-extension/116527 "2007-10-06T22:19:02Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![mahadewa](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/9e8a1a/32.png) [@mahadewa](https://www.ruby-forum.com/u/mahadewa)\
**Post date:** [October 6, 2007, 10:19pm UTC](https://www.ruby-forum.com/t/ann-variables-conditionals-extension/116527/1 "2007-10-06T22:19:02Z")

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Here’s a proof-of-concept extension that I’ve been working on. I  
originally  
hoped to have polished this all up but haven’t had the time for  
development.  
So, rather than stick it on a shelf, I thought I’d toss it out there in  
case  
it could benefit anyone. Besides, I want to find out what others in the  
Radiant community think =^D.

[http://swankinnovations.svnrepository.com/svn/open/radiant/extensions/vars\_if/](http://swankinnovations.svnrepository.com/svn/open/radiant/extensions/vars_if/)  
SVN Repository Location

Quickie Overview:  
This extension is essentially two extensions rolled into one. I just  
put  
them together for now for simplicity. It consists of:

1.) Abstracted Conditionals - instead of \<r:if\_myWhatever\> I’ve created  
generic \<r:if\> and \<r:unless\> tags that let you build your own  
conditional  
statements. Existing Radiant tags can be rewritten as such:

\<r:if\_content part=“my page part”\> becomes…  
\<r:if cond=“page.part[my page Part]”\>

and

\<r:if\_url matches=“regexp”\> becomes…  
\<r:if cond=“page[url] matches regexp”\>

But more importantly, a wider range of conditionals becomes possible  
such  
as:  
\<r:if cond=“page.part[my page Part] blank?”\> , or  
\<r:if cond=“page.part[my page Part] matches /myKeyword/”\>, or  
\<r:unless cond=“children[count] \> 10”\>

And, more important still, the goal is to allow extension developers to  
easily hook into this so that their own custom values can be used in  
conditionals. So, instead of creating new \<r:if\_newTagName\> tags, they  
could enable:

\<r:if cond=“myExtension[value] empty?”\> or  
\<r:if cond=“myCustomQuery[results] != myCustom[value]”\>

All they’d have to do is provide a method in their extension to resolve  
“myExtension[value]” for the conditionals to use.

2.) Abstracted ‘Puts’ Tag - because the conditionals must resolve  
symbols  
such as page[url] or MyExtension[value], I’ve also created a:

\<r:puts value="page[url] /\> (which is functionally the same as \<r:url  
/\>,  
or  
\<r:puts value="page[title] /\> (which is functionally the same as  
\<r:title/\>

and, of course, the extension developer can now instantly offer:

\<r:puts value=“myExtension[value]” /\>

3.) Variable Declaration - This one could be its own extenson. It  
provides  
a method to declare (store) variables in a local or global context  
(depending on whether its a single or double tag). These variables can  
then  
be displayed elsewhere (via \<r:puts\>) or evaluated (via \<r:if\> or  
\<r:unless\>).

Examples:  
Put it all together and the following becomes possible:

– in page body –  
\<r:store vars=“class:myClass; quote:‘my important string of text for  
quotation’; author:‘Chris P.’” /\>  
\<r:snippet name=“quote” /\>

– in snippet: quote –

 \<blockquote class=""\> 

– output –

> my important string of text for quotation

Chris P.

To learn more, check out the README file and the tag descriptions (in  
code  
or via Radiant). Plus I’ve tried to put extra comments in the code.

## What I’m hoping for: 1.) Feedback - does anybody else think that this would be useful or am I just out in left field. 2.) Suggestions - I have some blatant unresolved issues here that someone might see a good way to address (see the README for more). Ideas anyone? 3.) Improvements - at the moment the repository is read only but I’ll gladly accept patches, or even grant access for those that truly want to contribute.

View this message in context:  
[http://www.nabble.com/-ANN--Variables---Conditionals-Extension-tf4580441.html#a13075290](http://www.nabble.com/-ANN--Variables---Conditionals-Extension-tf4580441.html#a13075290)  
Sent from the Radiant - User mailing list archive at [Nabble.com](http://Nabble.com).

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**Author:** ![mahadewa](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/9e8a1a/32.png) [@mahadewa](https://www.ruby-forum.com/u/mahadewa)\
**Post date:** [October 6, 2007, 11:43pm UTC](https://www.ruby-forum.com/t/ann-variables-conditionals-extension/116527/2 "2007-10-06T23:43:58Z")

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doesn’t r:if conflict with back\_door ?

-mda

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**Author:** ![mahadewa](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/9e8a1a/32.png) [@mahadewa](https://www.ruby-forum.com/u/mahadewa)\
**Post date:** [October 7, 2007, 12:33am UTC](https://www.ruby-forum.com/t/ann-variables-conditionals-extension/116527/3 "2007-10-07T00:33:41Z")

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Mark D. Anderson wrote:

> doesn’t r:if conflict with back\_door ?
> 
> -mda

That would definitely depend on whether I knew what back\_door was 😛 .

Sorry for my ignorance – could someone give me some guidance here  
please?

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**Author:** ![mahadewa](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/9e8a1a/32.png) [@mahadewa](https://www.ruby-forum.com/u/mahadewa)\
**Post date:** [October 7, 2007, 2:18am UTC](https://www.ruby-forum.com/t/ann-variables-conditionals-extension/116527/4 "2007-10-07T02:18:16Z")

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Chris P. wrote:

> Sorry for my ignorance – could someone give me some guidance here please?

Nevermind, I found it – great minds, I guess. Wow, quit monitoring the  
group for a few months and look what happens…

Anyway, my objectives are a bit different than back\_door in that:

## 1.) There is NO WAY I want users to have full access to ruby. I wanted something as benign as \<r:if\_parent\> but more flexible. I wouldn’t build a site for a business and then hand the secretary or office staff that kind of a weapon. I’m not even sure I’d trust myself if the site was important

after all, there’s no way to test whether your code breaks your live  
site  
without breaking your live site (no real testing environment).

2.) I want something that designers and other non-coders could use. I  
don’t want them to have to learn ruby. My thoughts here are probably  
closer  
to John’s (can I say that?) when it comes to throwing in the kitchen  
sink –  
just enough and no more… done elegantly (by the way that phrase is now  
trademarked, John)

3.) I wanted to give the extension developer a way to easily expose  
values  
from their creations and use them in conditionals – yet also control  
what  
can be freely accessed and what is protected. Again, flexibility with  
security.

4.) I wanted something that was on a separate layer from the underlying  
ruby code. That way if Radiant 4.2.5 changes the way page titles are  
accessed, I only need to update my extension code – not all my static  
pages  
that now have Radiant-specific back\_door code.

5.) On a different note, the ‘vars’ stuff I created is different  
(though  
I’m sure that you could build that using back\_door and Ruby code).

Please don’t misunderstand me – I LIKE having back\_door available but  
the  
needs driving this are very different (hey, that’s why we have  
extensions).

## So, yes, it does conflict with the \<r:if\> and \<r:unless\> tags that Aitor created (I frankly love that he also used cond=“” – ha!) I suspect that most developers would opt for one OR the other, though, based on their security needs.

View this message in context:  
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Sent from the Radiant - User mailing list archive at [Nabble.com](http://Nabble.com).

---

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**Author:** ![mahadewa](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/9e8a1a/32.png) [@mahadewa](https://www.ruby-forum.com/u/mahadewa)\
**Post date:** [October 7, 2007, 6:54pm UTC](https://www.ruby-forum.com/t/ann-variables-conditionals-extension/116527/5 "2007-10-07T18:54:16Z")

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i think there is room for both, but personally I think it would be nice  
if you left  
the generic “r:if” tag to the full erb case in back\_door, for those who  
have both extensions  
loaded.  
(not that my opinion should count for much, having all of 1 week of  
experience  
with radiant).

-mda

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**Author:** ![mahadewa](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/9e8a1a/32.png) [@mahadewa](https://www.ruby-forum.com/u/mahadewa)\
**Post date:** [October 8, 2007, 12:17am UTC](https://www.ruby-forum.com/t/ann-variables-conditionals-extension/116527/6 "2007-10-08T00:17:43Z")

</div>

> i think there is room for both, but personally I think it would be  
> nice if you left the generic “r:if” tag to the full erb case in  
> back\_door, for those who have both extensions loaded.  
> (not that my opinion should count for much, having all of 1 week of  
> experience with radiant).

You would be able to do that yourself - if you load backdoor after  
the vars and conditions extension, the backdoor declaration of \<r:if\>  
should kick in.