perl -we'open FOO, "/dev/null";$x=<FOO>; print scalar $x'
perl -we'open FOO, "/dev/null"; print <FOO>'

##</code><code>##

perl -we'open FOO, "/dev/null"; $x=<FOO>; print $x+2'
perl -we'open FOO, "/dev/null"; $x=2+<FOO>; print $x'

##</code><code>##

perl -we'open FOO, "/dev/null"; print defined <FOO>'