how to set REST path for gcloud api in vibe.d?

[MichaelBi via Digitalmars-d-learn]

I need to use gcloud NLP api which has the url and endpoint like 
this 
"https://language.googleapis.com/v1beta2/documents:analyzeSentiment";. The ":" between documents and analyzeSentiment make a lot trouble for me. Just don't know how to setup the @path in RestInterface for such endpoint. I tried many, including `/documents:analyzeSentiment` but all failed, cannot go to the right path...

any idea? thank in advance.