Minor Description
Since Velocity2 is a Major version, why not start to support some new features?
As of Velocity 1.x you can use ${ name } to refer to object "name" in the context, or use $!
{ name }if you want "" for null values.
How about using ${{ el-expression }} to evaluate and output the given "el-expression" in a configured el-engine with the current velocity context, same should hold for $!{{ el-expression }}.
Some possible engines would be :
commons-el, commons-jexl, ognl, mvel
if using el/jexl ${{ name }} would be mostly the same as ${ name }.
usage cases:
the simple ${{ ... }} would allow more complicated expressions than present in the plain engine, especially if we look at the jexl2/3 features
#if( ${{ ... }} ) – would improve the boolean issue because the el could be used to wrap in "a?x:y"
architecture:
thru api abstraction, almost any el could be plugged in ( even groovy.eval or jsr223 )
core engine could ship with the api and el or jexl as the reference impl, other bindings would be optional jars with thier own deps.
brain storming:
how about supporting non-outputting el/jsr223 between #{{ ... #}} tags, like:
------
#{{ /* jexl code */
var = [ 1,2,3,4,5,6,7 ];
#}}
#foreach( $n in $var )
$n
#end
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