foo.cc:2:13: warning: character constant too long for its type
    2 |     writeln('hello, world');
      |             ^~~~~~~~~~~~~~
foo.cc:1:1: error: 'begin' does not name a type
    1 | begin
      | ^~~~~
foo.cc:3:1: error: 'end' does not name a type
    3 | end.
      | ^~~

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