I'm having trouble using back-references in a Windows one-liner and hoping someone knows what I'm doing wrong.

I can use a single back-reference but as soon as I try more than one it breaks.

Environment:

• Powershell on Windows 10 (because it's seemingly more sane than trying to use the standard Command prompt).
• Strawberry Perl (v5.26.0))

> echo "abcd" | perl -nle '/(b).(d)/ && print "$1" '
b
> echo "abcd" | perl -nle '/(b).(d)/ && print "$2" '
d
> echo "abcd" | perl -nle '/(b).(d)/ && print "$1 $2" '
Can't open $2 : No such file or directory.
[download]

The error changed when I tried to escape the double-quotes with a backslash and a back-tick:

> echo "abcd" | perl -nle '/(b).(d)/ && print \`"$1 $2\`" '
Can't find string terminator "`" anywhere before EOF at -e line 1.
[download]

Any ideas?

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