Also, if you used the -w switch, perl would have given three warnings that together make the error clear. 

Unquoted string "yes" may clash with future reserved word at -e line 1
+.
Name "main::yes" used only once: possible typo at -e line 1.
print() on unopened filehandle yes at -e line 1.

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In reply to Re: if -d by ambrus
in thread if -d by Anonymous Monk

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