sequence

inline fun <A> Iterable<Resource<A>>.sequence(): Resource<List<A>>

Sequences this Iterable of Resources. Iterable.map and sequence is equivalent to traverseResource.

import arrow.fx.coroutines.*

class File(url: String) {
suspend fun open(): File = this
suspend fun close(): Unit {}
override fun toString(): String = "This file contains some interesting content!"
}

suspend fun openFile(uri: String): File = File(uri).open()
suspend fun closeFile(file: File): Unit = file.close()
suspend fun fileToString(file: File): String = file.toString()

suspend fun main(): Unit {
//sampleStart
val res: List<String> = listOf(
"data.json",
"user.json",
"resource.json"
).map { uri ->
resource {
openFile(uri)
} release { file ->
closeFile(file)
}
}.sequence().use { files ->
files.map { fileToString(it) }
}
//sampleEnd
res.forEach(::println)
}