Create Sketch-PipelineOperator-WasOkayTest.md

Pwsh/Operators/Sketch-PipelineOperator-WasOkayTest.md

@@ -0,0 +1,57 @@
+```ps1
+function HandleStuff { 
+   process { 
+      if($_ -le 5) { 
+        write-verbose 'was <= ?' -Verbose
+        write-error 'invalid range' } 
+   }
+} 
+function Test-WasOk { '👍' }
+function GetFallback { 400 }
+```
+### Using `||` as a fallback ?
+
+```sh
+Can it run fallback when there's an error?
+0,3,10 | HandleStuff || GetFallback
+```
+output
+```
+VERBOSE: was <= ?
+HandleStuff: invalid range
+VERBOSE: was <= ?
+HandleStuff: invalid range
+```
+
+`GetFallback` is never called because the final value in the pipeline was not an error
+
+### Using `&&` to run command2 only if command1 is successful?
+
+0,3,10 | HandleStuff && Test-WasOk
+
+```ps1
+> 100 | HandleStuff && Test-WasOk
+# 👍
+
+> 3 | HandleStuff && Test-WasOk
+VERBOSE: was <= ?
+HandleStuff: invalid range
+👍
+```
+
+```ps1
+3, 10 | HandleStuff && Test-WasOk
+VERBOSE: was <= ?
+HandleStuff: invalid range
+👍
+Pwsh 7.4.1> [22] 🐒
+10, 3 | HandleStuff && Test-WasOk
+VERBOSE: was <= ?
+HandleStuff: invalid range
+👍
+Pwsh 7.4.1> [23] 🐒
+10, 3, 99 | HandleStuff && Test-WasOk
+VERBOSE: was <= ?
+HandleStuff: invalid range
+👍
+```