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Now let's look at operators that were introduced in PowerShell 7.

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First up is the chain operator.

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The chain operator is the two ampersands together.

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The way this works is if the left side expression is successful,

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such as get‑process ‑id $pid,

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then execute whatever is on the right side of the chain operator.

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So get‑process will run, I've got the process ID,

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and then I'm also going to display the number 100.

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Again, this is somewhat artificial,

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but I want you to be able to see what the operator is doing.

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And there is the result that you might expect to see in a PowerShell 7 session.

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There was the process, the process completed without error,

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and so the right side of the chain operator worked,

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and I get the value of 100.

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If the first command fails,

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then the second expression on the right side of the chain operator never runs.

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So I try to run get‑process for a nonexistent ID.

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I get an error.

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That command does not complete successfully,

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and so the second part of that chain does not run,

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and I never exceed the value of 100.

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The other chain operator is the two vertical bars put together.

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In this case,

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if the left side expression fails then run the right side expression.

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So if I do get‑process for some nonexistent process,

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because that fails then I get, in this case,

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the number 100.

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Here's an example of how you might use this in PowerShell.

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If the first test succeeds, then I want to do something.

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So, if I can do a test‑wsman on a computer,

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in this case my local computer name, then,

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that's the ampersand ampersand,

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then I'm going to run Get‑CimInstance and get the

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win32_bios class on that computer.

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So it's a nice example of using the chain operator.

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If the left side of the expression works,

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or runs without error I should say,

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then run whatever is on the right side of the chain operator.

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Now if you wanted, for example though, to get rid of say,

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I don't want to see that first command, you can pipe,

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this is going to pipe the test‑wsman to Out‑Null to suppress that test result.

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So all I get then is the result of the Get‑CimInstance command

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on the right side of the chain operator,

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the double ampersand.

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So here's an example where this is not going to work.

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So I'm going to try to test the $computer = "foo".

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That obviously doesn't exist.

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So if that works, then run Get‑CimInstance.

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And then if that doesn't work, then write a warning.

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So, I'm kind of combining both chain operators here.

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And so I get my failure, so I never run Get‑CimInstance,

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but because that first expression failed,

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then I get the warning.

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You'll, again, want to try these things all out for yourself.

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You could also do a lot of the same things in PowerShell

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scripting with an if/else statement. There is a help topic that you should take a look at.