Merge pull request #1269 from AllanWang/enhancement/coroutine-auth

Enhancement/coroutine

1 files changed, 20 insertions, 0 deletions

diff --git a/app/src/main/kotlin/com/pitchedapps/frost/utils/KotlinUtils.kt b/app/src/main/kotlin/com/pitchedapps/frost/utils/KotlinUtils.kt
new file mode 100644
index 00000000..320aeb69
--- /dev/null
+++ b/app/src/main/kotlin/com/pitchedapps/frost/utils/KotlinUtils.kt
@@ -0,0 +1,20 @@
+package com.pitchedapps.frost.utils
+
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.channels.ReceiveChannel
+import kotlinx.coroutines.channels.produce
+import kotlinx.coroutines.isActive
+
+@UseExperimental(ExperimentalCoroutinesApi::class)
+fun <T> ReceiveChannel<T>.uniqueOnly(scope: CoroutineScope): ReceiveChannel<T> = scope.produce {
+    var previous: T? = null
+    for (current in this@uniqueOnly) {
+        if (!scope.isActive) {
+            cancel()
+        } else if (previous != current) {
+            previous = current
+            send(current)
+        }
+    }
+}
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