For a full answer:

PS copied many concepts from Bash and Perl. (After all it's an attempt to fix problems with cmd and bat and full of aliases to support *nix commands)

For instance 

C:\tmp>powershell
Windows PowerShell
Copyright (C) Microsoft Corporation. Alle Rechte vorbehalten.


PS C:\tmp> $x="xxx"
PS C:\tmp> echo "a${x}b"
axxxb
PS C:\tmp> echo 'a${x}b'
a${x}b
PS C:\tmp> exit

C:\tmp>

[download]

That's why you need a single-quoted string for perl -e

Cheers Rolf
(addicted to the 𐍀𐌴𐍂𐌻 Programming Language :)
Wikisyntax for the Monastery

In reply to Re: $^O empty in windows powershell by LanX
in thread $^O empty in windows powershell by WithABeard

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