Perl says the -s is confusing. It also says "Unterminated <> operator". Look for where you've got a -s and an < together, and you should be able to trim it down to:

C:\temp>perl -e "print -s <= 2"
Warning: Use of "-s" without parentheses is ambiguous at -e line 1.
Unterminated <> operator at -e line 1.
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Go and add some disambiguating brackets, and everything is happy. For example

C:\temp>perl -e "print -s($_) <= 2"
1
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