Gmail-style search operators

My idea would be to have operators that can be entered in the search box, similar to Gmail.

For example, if I wanted to find everything with the label “Preface” right now, I type Preface into the search box and then drop down the selector list and choose to limit my search to labels. I have to switch this back to “all” for my next search.
Instead, I’d love to be able to search for:

label:Preface

No need to drop down the list, change my search preference, and no need to switch it back later.
It would also open up the possibility of more complex searches.

label:Preface status:Revised

For example.

Text entered without an operator would search against whatever the selected mode is in the current dropdown…

Thoughts?

That’s certainly a nice idea, and I like it. It would involve a fair bit of parsing and code to work with the current system, though, so I’ll keep this on the list for future thought - I have some ideas bubbling away about an improved search for version 3.0 (which admittedly is not even in the planning stages yet, just a bunch of blue-sky stuff I’d love to have in a future major update), so I’ll throw this in with my notes on that.

Thanks and all the best,
Keith