$ perl -le " package 3; "
syntax error at -e line 1, near "package 3;"
Execution of -e aborted due to compilation errors.

$ perl -le " $3::3 "
Bareword found where operator expected at -e line 1, near "$3::3"
        (Missing operator before ::3?)
syntax error at -e line 1, near "$3::3
"
Execution of -e aborted due to compilation errors.

$ perl -le " sub 3 { 3 } "
Illegal declaration of anonymous subroutine at -e line 1.