The library infrastructure » Overloading module
#include "diplib/overload.h"

Help with instantiating function templates and class templates for different pixel data types.

Contents

These preprocessor macros insert a block of code that calls or retrieves a function pointer to the right instance of a template, according to a dip::DataType argument (or create an object of a template class). For example, the code

DIP_OVL_CALL_ALL( myFunc, ( param1, param2 ), datatype );

causes a call to myFunc( param1, param2 ), where myFunc is a function template. The template will be specialized to whichever value the variable datatype has at run time. The compiler generates instances of your template for all possible values of datatype. If you want to restrict the allowed data types, use a macro ending in other than _ALL. For example, the macro DIP_OVL_CALL_REAL only allows integer and floating point data types (not binary nor complex types).

Note that the function parameters are the same for all instances of the template function; the template parameter is not used in the function’s parameter list. This is the only way that generic code (i.e. code that works with pixels of any data type) can work. You can think of param1 above being of type void* or dip::Image, for example.

DIP_OVL_NEW_ALL and friends work similarly, but create a new object of a template class with operator new. For such an assignment to work, the template class must have a base class that is not a template, and the object must be referred to through a pointer to its base class. The result of new is cast to the declaration type of the variable being assigned to, so that one can assign e.g. into a std::unique_ptr.

There are four groups of macros defined in diplib/overload.h:

  • DIP_OVL_CALL_xxx calls a function, discarding any return value.
  • DIP_OVL_CALL_ASSIGN_xxx calls a function, assigning the return value in a variable.
  • DIP_OVL_ASSIGN_xxx assigns a function pointer to a variable, without calling the function.
  • DIP_OVL_NEW_xxx allocates an object of a templated class, assigns to pointer to a variable.

Each of the four groups of macros exist in the following flavors:

Macro name xxx Corresponding dip::DataType::Classes value
BIN dip::DataType::Class_Binary
UINT dip::DataType::Class_UInt
SINT dip::DataType::Class_SInt
INTEGER dip::DataType::Class_Integer
INT_OR_BIN dip::DataType::Class_IntOrBin
FLOAT dip::DataType::Class_Float
COMPLEX dip::DataType::Class_Complex
FLEX dip::DataType::Class_Flex
FLEXBIN dip::DataType::Class_FlexBin
UNSIGNED dip::DataType::Class_Unsigned
SIGNED dip::DataType::Class_Signed
REAL dip::DataType::Class_Real
SIGNEDREAL dip::DataType::Class_SignedReal
NONBINARY dip::DataType::Class_NonBinary
NONCOMPLEX dip::DataType::Class_NonComplex
ALL dip::DataType::Class_All

Macros

#define DIP_OVL_CALL_BINARY
Calls the overloaded function for the binary type.
#define DIP_OVL_CALL_UINT
Calls the overloaded function for all unsigned integer types.
#define DIP_OVL_CALL_SINT
Calls the overloaded function for all signed integer types.
#define DIP_OVL_CALL_FLOAT
Calls the overloaded function for all float types.
#define DIP_OVL_CALL_COMPLEX
Calls the overloaded function for all complex types.
#define DIP_OVL_CALL_INTEGER
Calls the overloaded function for all integer types.
#define DIP_OVL_CALL_INT_OR_BIN
Calls the overloaded function for all integer and binary types.
#define DIP_OVL_CALL_UNSIGNED
Calls the overloaded function for all unsigned types.
#define DIP_OVL_CALL_SIGNED
Calls the overloaded function for all signed (integer + float + complex) types.
#define DIP_OVL_CALL_REAL
Calls the overloaded function for all real (integer + float) types.
#define DIP_OVL_CALL_SIGNEDREAL
Calls the overloaded function for all signed real (integer + float) types.
#define DIP_OVL_CALL_NONCOMPLEX
Calls the overloaded function for all non-complex types.
#define DIP_OVL_CALL_FLEX
Calls the overloaded function for all floating-point and complex types.
#define DIP_OVL_CALL_FLEXBIN
Calls the overloaded function for all floating-point, complex and binary types.
#define DIP_OVL_CALL_NONBINARY
Calls the overloaded function for all types but binary.
#define DIP_OVL_CALL_ALL
Calls the overloaded function for all types.
#define DIP_OVL_CALL_ASSIGN_BINARY
Calls the overloaded function for the binary type, and assigns the output value to variable x.
#define DIP_OVL_CALL_ASSIGN_UINT
Calls the overloaded function for all unsigned integer types, and assigns the output value to variable x.
#define DIP_OVL_CALL_ASSIGN_SINT
Calls the overloaded function for all signed integer types, and assigns the output value to variable x.
#define DIP_OVL_CALL_ASSIGN_FLOAT
Calls the overloaded function for all float types, and assigns the output value to variable x.
#define DIP_OVL_CALL_ASSIGN_COMPLEX
Calls the overloaded function for all complex types, and assigns the output value to variable x.
#define DIP_OVL_CALL_ASSIGN_INTEGER
Calls the overloaded function for all integer types, and assigns the output value to variable x.
#define DIP_OVL_CALL_ASSIGN_INT_OR_BIN
Calls the overloaded function for all integer and binary types, and assigns the output value to variable x.
#define DIP_OVL_CALL_ASSIGN_UNSIGNED
Calls the overloaded function function for all unsigned types, and assigns the output value to variable x.
#define DIP_OVL_CALL_ASSIGN_SIGNED
Calls the overloaded function for all signed (integer + float + complex) types, and assigns the output value to variable x.
#define DIP_OVL_CALL_ASSIGN_REAL
Calls the overloaded function for all real (integer + float) types, and assigns the output value to variable x.
#define DIP_OVL_CALL_ASSIGN_SIGNEDREAL
Calls the overloaded function for all signed real (integer + float) types, and assigns the output value to variable x.
#define DIP_OVL_CALL_ASSIGN_NONCOMPLEX
Calls the overloaded function for all non-complex types, and assigns the output value to variable x.
#define DIP_OVL_CALL_ASSIGN_FLEX
Calls the overloaded function for all floating-point and complex types, and assigns the output value to variable x.
#define DIP_OVL_CALL_ASSIGN_FLEXBIN
Calls the overloaded function for all floating-point, complex and binary types, and assigns the output value to variable x.
#define DIP_OVL_CALL_ASSIGN_NONBINARY
Calls the overloaded function for all types but binary, and assigns the output value to variable x.
#define DIP_OVL_CALL_ASSIGN_ALL
Calls the overloaded function for all types, and assigns the output value to variable x.
#define DIP_OVL_ASSIGN_BINARY
Assigns a pointer to the overloaded function for the binary type to the variable f.
#define DIP_OVL_ASSIGN_UINT
Assigns a pointer to the overloaded function for all unsigned integer types to the variable f.
#define DIP_OVL_ASSIGN_SINT
Assigns a pointer to the overloaded function for all signed integer types to the variable f.
#define DIP_OVL_ASSIGN_FLOAT
Assigns a pointer to the overloaded function for all float types to the variable f.
#define DIP_OVL_ASSIGN_COMPLEX
Assigns a pointer to the overloaded function for all complex types to the variable f.
#define DIP_OVL_ASSIGN_INTEGER
Assigns a pointer to the overloaded function for all integer types to the variable f.
#define DIP_OVL_ASSIGN_INT_OR_BIN
Assigns a pointer to the overloaded function for all integer and binary types to the variable f.
#define DIP_OVL_ASSIGN_UNSIGNED
Assigns a pointer to the overloaded function for all unsigned types to the variable f.
#define DIP_OVL_ASSIGN_SIGNED
Assigns a pointer to the overloaded function for all signed (integer + float + complex) types to the variable f.
#define DIP_OVL_ASSIGN_REAL
Assigns a pointer to the overloaded function for all real (integer + float) types to the variable f.
#define DIP_OVL_ASSIGN_SIGNEDREAL
Assigns a pointer to the overloaded function for all signed real (integer + float) types to the variable f.
#define DIP_OVL_ASSIGN_NONCOMPLEX
Assigns a pointer to the overloaded function for all non-complex types to the variable f.
#define DIP_OVL_ASSIGN_FLEX
Assigns a pointer to the overloaded function for all floating-point and complex types to the variable f.
#define DIP_OVL_ASSIGN_FLEXBIN
Assigns a pointer to the overloaded function for all floating-point, complex and binary types to the variable f.
#define DIP_OVL_ASSIGN_NONBINARY
Assigns a pointer to the overloaded function for all types but binary to the variable f.
#define DIP_OVL_ASSIGN_ALL
Assigns a pointer to the overloaded function for all types to the variable f.
#define DIP_OVL_NEW_BINARY
Assigns a pointer to the overloaded class for the binary type to the variable x.
#define DIP_OVL_NEW_UINT
Assigns a pointer to the overloaded class for all unsigned integer types to the variable x.
#define DIP_OVL_NEW_SINT
Assigns a pointer to the overloaded class for all signed integer types to the variable x.
#define DIP_OVL_NEW_FLOAT
Assigns a pointer to the overloaded class for all float types to the variable x.
#define DIP_OVL_NEW_COMPLEX
Assigns a pointer to the overloaded class for all complex types to the variable x.
#define DIP_OVL_NEW_INTEGER
Assigns a pointer to the overloaded class for all integer types to the variable x.
#define DIP_OVL_NEW_INT_OR_BIN
Assigns a pointer to the overloaded class for all integer and binary types to the variable x.
#define DIP_OVL_NEW_UNSIGNED
Assigns a pointer to the overloaded class for all unsigned types to the variable x.
#define DIP_OVL_NEW_SIGNED
Assigns a pointer to the overloaded class for all signed (integer + float + complex) types to the variable x.
#define DIP_OVL_NEW_REAL
Assigns a pointer to the overloaded class for all real (integer + float) types to the variable x.
#define DIP_OVL_NEW_SIGNEDREAL
Assigns a pointer to the overloaded class for all signed real (integer + float) types to the variable x.
#define DIP_OVL_NEW_NONCOMPLEX
Assigns a pointer to the overloaded class for all non-complex types to the variable x.
#define DIP_OVL_NEW_FLEX
Assigns a pointer to the overloaded class for all floating-point and complex types to the variable x.
#define DIP_OVL_NEW_FLEXBIN
Assigns a pointer to the overloaded class for all floating-point, complex and binary types to the variable x.
#define DIP_OVL_NEW_NONBINARY
Assigns a pointer to the overloaded class for all types but binary to the variable x.
#define DIP_OVL_NEW_ALL
Assigns a pointer to the overloaded class for all types to the variable x.