Add shorthand sessionOf and transactionOf

[Koriit]

Additional shorthand sessionOf that doesn't need to be wrapped with using.

Plus transactionOf as often times you need a transaction for the whole session and with this you don't need to nest transaction block in session block.

With this I believe it cannot get any better with the amount of control and readability it offers:

val ds : DataSource by instance() // kodein

sessionOf(ds) { session ->
  // ...
}

transactionOf(ds) { tx ->
  // ...
}

[Koriit]

I think install-jdk.sh doesn't support JDK8 anymore.

[seratch]

Sorry for my late response here.

[seratch]

Using the same name sessionOf here is very confusing. Is there a better name for this? I think withSession may be okay but I'm not so confident.

[Koriit]

How, about changing it to extension functions:

fun <T> DataSource.session(...

fun <T> DataSource.transaction(...

Usage would be now:

val db: DataSource
db.session {

}

db.transaction {

}

I agree that reusing the name sessionOf might be confusing. Furthermore, when I used it in my project I noticed that IDE has slight problems with finding proper imports.

[seratch]

How about having use method for AutoCloseable as with kotlin.io.use?
https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.io/use.html

Or, I haven't checked in detail yet but if implementing both Closeable and AutoCloseable is fine, we can just use kotlin.io.use by implementing Closeable.

[Koriit]

That would also be awesome too - maybe even better. Though, I would still like to see a shorthand function like the transactionOf above.

[seratch]

Let me close this PR. Please consider going with your own utility for shorthand.