For those looking for something similar for Zsh, there is larkey’s excellent work: https://github.com/larkery/zsh-histdb

There’s also the wonderful rash: https://pypi.python.org/pypi/rash

I looked at elvish the other day and poked around and discovered that it does this by default. I shook my head at the switch away from grep’ability, then thought about it and decided that it was absolutely the right call to make (especially if you look at multiple shells, concurrency, and meta/unmeta for zsh to mangle what’s actually stored).