cast or function pointer or something else?

[lilzz]

1

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******************************************************************************/
MLCIStream& MLCIStream::operator>>(istream& (*manipulator)(istream&))

void MLCOStream::external_ctor(const MString& description, char* buf, int
                               nBytes)
{
   VERIFY_ISTREAM(*this, manipulator);
}

what's this (stream&(*manipulator)(stream&))?
this (*manipulator) a cast or function pointer? I couldn't tell what it is.



2

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if defined(GNU)
 
  typedef void (*new_handler)();
  extern "C" new_handler set_new_handler (new_handler);

if new_handler is a function pointer, then new_handler set_new_handler (new_handler) means it returns a function pointer and takes in a function pointer as param?

3

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void out_of_memory_handler()
{
 ....}

 set_new_handler(out_of_memory_handler);

shouldn't that be out_memory_hanfler()?

4

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Bool operator==(const MString& str1, const char* str2)
{
   return (strcmp(str1.str, str2) == 0);
}

why one string use & and another use *?

5

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MString::MString(const char* source, int first)
   : refCount(1)

i normally think : is for base class for inheritance, but :refCount is not. so what does : means in this case?

[AndyD]

1

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******************************************************************************/
MLCIStream& MLCIStream::operator>>(istream& (*manipulator)(istream&))

void MLCOStream::external_ctor(const MString& description, char* buf, int
                               nBytes)
{
   VERIFY_ISTREAM(*this, manipulator);
}

what's this (stream&(*manipulator)(stream&))?
this (*manipulator) a cast or function pointer? I couldn't tell what it is.

manipulator is a pointer to function that takes one argument (a reference to a stream object) and returns a reference to a stream object. As the name suggests it is a stream manipulator.

2

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if defined(GNU)
 
  typedef void (*new_handler)();
  extern "C" new_handler set_new_handler (new_handler);

if new_handler is a function pointer, then new_handler set_new_handler (new_handler) means it returns a function pointer and takes in a function pointer as param?

Yes, it is code to change the new handler. It sets the new handler using the function pointer passed in and returns the previous new handler, so that you can go back to the previous behaviour.

3

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void out_of_memory_handler()
{
 ....}

 set_new_handler(out_of_memory_handler);

shouldn't that be out_memory_hanfler()?

The name suggests it handles the situations when the program runs out of memory. I am not sure what you mean by hanfler

4

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Bool operator==(const MString& str1, const char* str2)
{
   return (strcmp(str1.str, str2) == 0);
}

why one string use & and another use *?

MString is a class that represents a string, while const char* is a C style string. A C style string is simply a a char* (pointer), while MString is a class so it is passed by reference to avoid making a copy.

5

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MString::MString(const char* source, int first)
   : refCount(1)

i normally think : is for base class for inheritance, but :refCount is not. so what does : means in this case?

This is a member initialization list.