Merge branch 'main' of https://github.com/ninmonkey/ninMonkQuery-examples

Author: ninmonkey

WebRequests/pq/Lazy Eval Can Skip API Calls If Not Required.pq

@@ -0,0 +1,31 @@
+let
+    /*
+    See more: 
+    - [Dynamic, Lazy Records](https://bengribaudo.com/blog/2021/08/09/5941/dynamic-lazy-records)
+
+    */
+    // example showing that Api1() isn't always called
+    // if they are called, it will delay for 3 seconds to simulate a query or web request
+    // skip load ends up skipping the query, and the 3 second delay
+    delay   = #duration(0,0,0, 3),
+    SkipLoad = true,
+    
+    // sleep for delay Seconds and return a string
+    Api1 = () => Function.InvokeAfter( 
+        () => "Api1 finished", delay ),
+
+    // for fun, this version uses a string template to create the error rmessage 
+    Api2 =() => Function.InvokeAfter( 
+        () => 
+            Text.Format(
+                "Api2 finished, at #[dt]", 
+                [ dt = DateTime.LocalNow() ]
+            ), 
+            delay ),
+    
+    // the important part of the query:
+    ApiList = { Api1(), Api2() },
+    Query2 = { "some", "Fallback" },
+    Final = if SkipLoad = true then Query2 else ApiList
+in
+    Final