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Estimatd hours taken: 0.5 Branches: main samples/*.m: Use '.' as the module qualifier instead of '__'. Use the new foreign language interface. Fix minor formatting issues. Use state variables for passing the I/O state.
34 lines
1.1 KiB
Mathematica
34 lines
1.1 KiB
Mathematica
% This module cpp_main_int defines a Mercury predicate cpp_main which acts as an
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% interface to the C++ function cpp_main(), which is defined in cpp_main.c.
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% This source file is hereby placed in the public domain. -fjh (the author).
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:- module cpp_main_int.
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:- interface.
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:- import_module io.
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% Since the cpp_main() function has side effects, we declare the corresponding
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% Mercury predicate as one that takes an io__state pair. If we didn't do
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% this, the Mercury compiler might optimize away calls to it!
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:- pred cpp_main(io::di, io::uo) is det.
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:- implementation.
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% #include the header file containing the function prototype
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% for cpp_main(), using a `pragma c_header_code' declaration.
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% Note that any double quotes or backslashes in the C code for
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% the `#include' line must be escaped, since the C code is
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% given as a Mercury string.
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:- pragma foreign_decl("C", "#include \"cpp_main.h\"").
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% Define the Mercury predicate cpp_main to call the C++ function
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% cpp_main.
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:- pragma foreign_proc("C",
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cpp_main(IO0::di, IO::uo),
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[may_call_mercury, promise_pure],
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"
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cpp_main();
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IO = IO0;
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").
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