I want to support the user typing in a filter, then as token values are matched I'll highlight them (similar to the github search feature if you put repo:value and value gets highlighted. But at any point they might not have a valid expression to parse.

I'm totally green in parser/lexers/grammars, but is there any support for that? To ignore errors but parse as much as possible?

The behavior I'm looking to replicate is below. I put a space in repo: and that basically disabled that token, but still parsed the rest.