Look for explicit statement in job offer or just send question before applying, I did that many times and usually got some response. If you don't get any response then it means that it was not worth applying anyway. :)
Is it worth trying?
Should you show at home learning and dev of the Lang?
Do you only apply as intermediate or junior regardless of other development experience?
Depends. Startups likely will not have the flexibility to allow for R&D. Large companies likely will have the financial flexibility for R&D, and will expect you to publish/share your discoveries.<p>There's also all sorts of circumstantial conditions for which anyone would hire you, for instance, if you have a radically unique background that no one could possibly let walk out the door.