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Diffstat (limited to 'share/swig/2.0.11/python/typemaps.i')
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diff --git a/share/swig/2.0.11/python/typemaps.i b/share/swig/2.0.11/python/typemaps.i new file mode 100644 index 0000000..5d438ec --- /dev/null +++ b/share/swig/2.0.11/python/typemaps.i @@ -0,0 +1,148 @@ +/* ----------------------------------------------------------------------------- + * typemaps.i + * + * Pointer handling + * These mappings provide support for input/output arguments and common + * uses for C/C++ pointers. + * ----------------------------------------------------------------------------- */ + +// INPUT typemaps. +// These remap a C pointer to be an "INPUT" value which is passed by value +// instead of reference. + +/* +The following methods can be applied to turn a pointer into a simple +"input" value. That is, instead of passing a pointer to an object, +you would use a real value instead. + + int *INPUT + short *INPUT + long *INPUT + long long *INPUT + unsigned int *INPUT + unsigned short *INPUT + unsigned long *INPUT + unsigned long long *INPUT + unsigned char *INPUT + bool *INPUT + float *INPUT + double *INPUT + +To use these, suppose you had a C function like this : + + double fadd(double *a, double *b) { + return *a+*b; + } + +You could wrap it with SWIG as follows : + + %include <typemaps.i> + double fadd(double *INPUT, double *INPUT); + +or you can use the %apply directive : + + %include <typemaps.i> + %apply double *INPUT { double *a, double *b }; + double fadd(double *a, double *b); + +*/ + +// OUTPUT typemaps. These typemaps are used for parameters that +// are output only. The output value is appended to the result as +// a list element. + +/* +The following methods can be applied to turn a pointer into an "output" +value. When calling a function, no input value would be given for +a parameter, but an output value would be returned. In the case of +multiple output values, they are returned in the form of a Python tuple. + + int *OUTPUT + short *OUTPUT + long *OUTPUT + long long *OUTPUT + unsigned int *OUTPUT + unsigned short *OUTPUT + unsigned long *OUTPUT + unsigned long long *OUTPUT + unsigned char *OUTPUT + bool *OUTPUT + float *OUTPUT + double *OUTPUT + +For example, suppose you were trying to wrap the modf() function in the +C math library which splits x into integral and fractional parts (and +returns the integer part in one of its parameters).K: + + double modf(double x, double *ip); + +You could wrap it with SWIG as follows : + + %include <typemaps.i> + double modf(double x, double *OUTPUT); + +or you can use the %apply directive : + + %include <typemaps.i> + %apply double *OUTPUT { double *ip }; + double modf(double x, double *ip); + +The Python output of the function would be a tuple containing both +output values. + +*/ + +// INOUT +// Mappings for an argument that is both an input and output +// parameter + +/* +The following methods can be applied to make a function parameter both +an input and output value. This combines the behavior of both the +"INPUT" and "OUTPUT" methods described earlier. Output values are +returned in the form of a Python tuple. + + int *INOUT + short *INOUT + long *INOUT + long long *INOUT + unsigned int *INOUT + unsigned short *INOUT + unsigned long *INOUT + unsigned long long *INOUT + unsigned char *INOUT + bool *INOUT + float *INOUT + double *INOUT + +For example, suppose you were trying to wrap the following function : + + void neg(double *x) { + *x = -(*x); + } + +You could wrap it with SWIG as follows : + + %include <typemaps.i> + void neg(double *INOUT); + +or you can use the %apply directive : + + %include <typemaps.i> + %apply double *INOUT { double *x }; + void neg(double *x); + +Unlike C, this mapping does not directly modify the input value (since +this makes no sense in Python). Rather, the modified input value shows +up as the return value of the function. Thus, to apply this function +to a Python variable you might do this : + + x = neg(x) + +Note : previous versions of SWIG used the symbol 'BOTH' to mark +input/output arguments. This is still supported, but will be slowly +phased out in future releases. + +*/ + +%include <typemaps/typemaps.swg> |