Well, you cannot (unless you want to include fatal (run time) errors in 'not getting the same result'). 
$ perl -wE 'sub for {say "Hello"} &for'
Hello
$ perl -wE 'sub foreach {say "Hello"} &for'
Undefined subroutine &main::for called at -e line 1.

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In reply to Re^4: using foreach with a regex by JavaFan
in thread using foreach with a regex by Anonymous Monk

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