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PowerShell 3 behavioural change

It's taken me way too long to get into PowerShell 3, I guess opportunity hasn't shown it's self until now and so, here, my V3 journey begins.

I was asked to debug a script that would run fine in PS v2 and not in v3.  The issue was a that a variable length was being checked and was failing in v3.  This is why...

In v2 if a variable is undefined, this test returns false

PS C:\windows\system32> $var.length -eq 0
False

In v3 the same test returns true....

PS C:\windows\system32> $var.length -eq 0
True

Not a biggie, but as in this case, a script has broken so something to consider!

cheers

Adam
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