$ python -c 'print("START"); print(x + y)'
START
Traceback (most recent call last):
  File "<string>", line 1, in <module>
NameError: name 'x' is not defined

$ perl -E 'use strict; say "START"; say $x + $y'
Global symbol "$x" requires explicit package name (did you forget to declare "my $x"?) at -e line 1.
Global symbol "$y" requires explicit package name (did you forget to declare "my $y"?) at -e line 1.
Execution of -e aborted due to compilation errors.