[Suggestion] Type state pattern for transactions

[acul009]

Hi,

I'm coming from go and was looking for something similar to boltdb.
After finding your project and starting to learn rust, I wanted to ask if it would be feasible to implement the typestate pattern for transactions.

Instead of just allowing to call tx() with a bool you could also call ro() or rw() which would give a transaction without any of the write functions even available. That way you could catch these errors at compiler time.

If you think this is a good idea, I'd be happy to do a bit of gruntwork for adding the state to each neccesary type.
I don't think I can handle all problems however, so I'd be grateful for some help later on.

I would suggest these 3 TypeStates:

• Legacy (would be used when tx is called)
• ReadOnly
• WriteOnly

This way other projects will still function, while enabling compiler type checking the transaction type.