I've created an issue with the same requirement. Typically you should create an alternative helper which should accept inner blocks, and this helper will internally call @size
helper.
Let's name it @sizeOf
:
dust.helpers.sizeOf = function(chunk, context, bodies, params) {
var value = this.size(chunk, context, bodies, params);
return (bodies && bodies.block) ? chunk.render(bodies.block, context.push({ isSelect: true, isResolved: false, selectKey: value })) : value;
};
And we should use it like this:
{@sizeOf key=items}
{@gt value=0}
asdf
{/gt}
{/size}