Parser now builds expressions that can detect promises and transparently
evaluate them to undefined or the promise value.
If promiseA is resolved with value 'A', then {{promiseA}} evals to 'A';
If promiseA is unresolved, then {{promiseA}} evals to undefined;
Following invocations are supported:
- {{promise}}
- {{promise.futureProp}}
- {{[promise][0]}}
- {{object.promise}}
- {{object[promise]}}
- {{array[promise]}}
- {{fn(promise)}}
- combinations of the above
