Suspending function in curly brackets

[recursive-rat4]

I have a following code with version 4.0.1

suspend fun bar(): Int

suspend fun baz() {
    logger.info("Foo ${bar()}")
}

Now that version 5.0.0 deprecates round brackets, a straight conversion doesn't work, because it loses the suspension.

    logger.info { "Foo ${bar()}" }
    // e: Suspension functions can be called only within coroutine body

Would be a recommended way to wrap the suspending call into runBlocking like this?

    logger.info { "Foo ${runBlocking { bar() }}" }

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[oshai]

I wouldn't use runBlocking() as it will block the thread.
if you want it to work like before it should be translated to:

val barMessage = bar()
logger.info { "Foo $barMessage" }

(There is another question here which is why a log message computation will be a suspended operation).

[recursive-rat4]

I wouldn't use runBlocking() as it will block the thread.

Thanks, I overlooked this detail.

There is another question here which is why a log message computation will be a suspended operation

Mutexes, mutexes everywhere.

[ivan-osipov]

@oshai
A practical problem that if you want to log extended context and load this data from your db, the method of loading is suspendable

so, for example, now you should do something like that

if(logger.isDebugEnabled()) { // or even trace
  val extraContext = loadMoreContext() // suspend func call
  logger.debug("Oops! Here is more context $extraContext")
}

instead of something like that

logger.coDebug { "Oops! Here is more context ${loadMoreContext()}" }