Error(s):

source_file.cpp:10:12: error: no viable conversion from returned value of type 'Optional' to function return type 'bool'
    return op;
           ^~
source_file.cpp:24:10: error: redefinition of 'b'
    bool b = get_value_2();
         ^
source_file.cpp:22:10: note: previous definition is here
    bool b = get_value();
         ^
2 errors generated.