These functions can be used in external code with OpenMaple or define_external.

The MapleTo* functions convert a Maple object to a hardware data structure format.  The return values are defined in the supplied header files.

Floating-point numbers may lose precision during the conversion to hardware size data.

Conversion from a Maple string object to an integer returns the ASCII value of the first character in that string.  Conversion from a Maple boolean to an integer returns 1 for true, 0 for false, and -1 for FAIL.

The C version of MapleToString returns the same character array pointer referenced in the given Maple object. This string must not be modified in-place. Modifications must be made on a copy, not the original string returned by MapleToString.

The MapleToPointer conversion returns the pointer given as the first argument of ToMaplePointer. For more information about this data structure, see ?MaplePointer.

Some native types are defined in the header file mplshlib.h.  The types M_INT and M_BOOL are often used for word-sized integer and boolean values. Other types are defined in mpltable.h, including complex structs, and macros for fixed bit size integers.

$\mathrm{with}\left(\mathrm{ExternalCalling}\right)\:$

$\mathrm{dll}≔\mathrm{ExternalLibraryName}\left(''HelpExamples''\right)\:$

$\mathrm{cmp}≔\mathrm{DefineExternal}\left(''MyCompare''\,\mathrm{dll}\right)\:$

$\mathrm{cmp}\left(''>''\,3.13\,3.14\right)$

Comparing 3.130000 > 3.140000

$\mathrm{false}$

$\mathrm{cmp}\left(''=''\,\mathrm{evalf}\left(\mathrm{\pi }\,30\right)\,\mathrm{evalf}\left(\mathrm{\pi }\,40\right)\right)$

Comparing 3.141593 = 3.141593

$\mathrm{true}$

$\mathrm{cmp}\left(''!=''\,1\,0\right)$

Comparing 1.000000 != 0.000000

$\mathrm{FAIL}$