Add a oncePerRefresh function.

Author: nedtwigg

src/lib/once-per-refresh.ts

@@ -0,0 +1,13 @@
+const hasRunSinceTheLastFullPageload = new Set<string>()
+
+/**
+ * This function helps you run a given function only once per full pageload.
+ * So this will not run again due to turbolink navigation.
+ */
+export function oncePerRefresh(key: string, fun: () => void) {
+  if (hasRunSinceTheLastFullPageload.has(key)) {
+    return
+  }
+  fun()
+  hasRunSinceTheLastFullPageload.add(key)
+}