= Variables

The Variables Extension adds the ability to declare and retrieve variables from
within Radiant pages (and snippets and layouts).

It enhances <r:snippet> and <r:content> tags to let them declare variables
(similar to parameterized snippets).

And finally, it adds an evaluator for use by the Conditional Tags extension so 
you can do things like:

  -- in your body part --
    <r:content part="extended" class="someClass" />
    
  -- in your extended part --
    <p<r:if cond="vars[class] exists?"> class="<r:puts value_for="vars[class]" />">
      Some Text
    </p>



== The 'set_vars' Tag

The new 'set_vars' tag is used to set variable values as in:

    <r:set_vars a="my string" b="false" />

The values are cast as either a number, boolean, nil, or string. Variables set
this way are global in scope and can be accessed from anywhere.


== The 'snippet' and 'content' Tags

The 'snippet' and 'content' tags have been modified to allow variables to be
declared as well, like:

    <r:snippet name="a snippet" myVar="some value" />
    <r:content part="a part" a="10" b="nil" c="false" />

As with 'set_vars', the variables are cast into a type.  UNLIKE 'set_vars' these
variables are local (contextual) in scope and are only available within the
snippet or page part (or sub-contexts).

Note: Local variables declarations do not overwrite global ones but they do
supercede them.


== The Vars Evaluator

There is also a 'vars' evaluator implemented to work with the Conditional Tags
extension like.

    <r:if cond=" vars[class] exists? " > You have no class ;-) </r:if>

At this time Conditional Tags is required (though you could disable it).