So what happens if the inventor decides to publish the invention in a manner that implies that it's free for others to use without any license or royalty, but t

So what happens if the inventor decides to publish the invention in a manner that implies that it's free for others to use without any license or royalty, but then, a year later, decides to file for a patent? Would the use of the invention by others invalidate the patent application? Would the patent be granted, but unenforceable due to the prior public release of the invention being construed as estoppel that creates a general license to the invention? Or would the inventor, armed with a new patent, be able to tell everyone already using the invention that they now have to pay a license fee to continue using it?