Question

Curious, what is the idea behind this:

@() -as [bool] # False  @($null) -as [bool]  # False  @($null, $null) -as [bool] # True 

I would expect either False/True/True or False/False/False, but not False/False/True.

Answer 1

As outlined in the Powershell Quick reference¹:

 True                                                 False  ~~~~                                                 ~~~~~ $TRUE                                                $FALSE  Any string of length > 0, except the word “false”    Empty string or the string “false”  Any number ≠ 0                                       Any number = 0  Array of length > 1                                  Array of length 0  Array of length 1 whose element is true              Array of length 1 whose element is false  A reference to any object                            Null  

I think the idea behind it was that an array with just one element $false can easily happen if you put the output of a cmdlet/function into an array. You might expect more values but some error made it to return $false, but $false twice in the array might be unlikely in that case.

Or maybe we should wait for Jeffrey Snover to answer here 🙂

¹ C:\Windows\System32\WindowsPowerShell\v1.0\Documents\en-US\QuadFold.rtf on my machine