foo.cc: In function 'int Fun(int)':
foo.cc:7:1: error: a function-definition is not allowed here before '{' token
    7 | {
      | ^
foo.cc:12:1: error: expected '}' at end of input
   12 | }
      | ^
foo.cc:4:1: note: to match this '{'
    4 | {
      | ^

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