On 2013-07-18 00:59, H. S. Teoh wrote:
IOW either you don't do it at all, or you have to go all the way and
implement a fully-functional C frontend?
If so, libclang is starting to sound rather attractive...
That's what I'm telling
Hmm. We *could* pre-preprocess the code to do this conversion first to
pick out these #define's, then suppress the #define's we understand from
the input to the C preprocessor. Something like this:
bool isSimpleValue(string s) {
// basically, return true if s is something compilable
// when put on the right side of "enum x = ...".
}
auto pipe = spawnCPreprocessor();
string[string] manifestConstants;
foreach (line; inputFile.byLine()) {
if (auto m=match(line, `^\s*#define\s+(\w+)\s+(.*?)\s+`))
{
if (isSimpleValue(m.captures[2])) {
manifestConstants[m.captures[1]] =
m.captures[2];
// Suppress enums that we picked out
continue;
}
// whatever we don't understand, hand over to
// the C preprocessor
}
pipe.writeln(line);
}
Basically, whatever #define's we can understand, we handle, and anything
else we let the C preprocessor deal with. By suppressing the #define's
we've picked out, we force the C preprocessor to leave any reference to
them as unexpanded identifiers, so that later on we can just generate
the enums and the resulting code will match up correctly.
You will just end up needing to build a full C preprocessor. Just use an
existing one, that is libclang.
--
/Jacob Carlborg
