Note that in many cases this conversion is already done. The Gnucash XML does this in most cases. Take a look at, e.g. src/engine/Account.c for an example. It's not _quite_ as clever as your code, but it does the job.
And yes, we should definitely be using strings instead of ints for enums. Remember when I asked why you needed QOF_TYPE_INT32? ;) I dont think we ever use an INT64 enum. -derek Quoting Neil Williams <[EMAIL PROTECTED]>: > That anti-software patent meeting has had an unexpected side effect. After > the > meeting, I got chatting about GnuCash and my development work on QOF (as you > > do). One of the results was a discussion about how to turn enum values > (integers) into strings (for text file readability) using #define. > > I experimented with the code that had been jotted down on the back of EU > software patent EP 0760140 (!) and also found this example: > http://www.flipcode.com/cgi-bin/fcmsg.cgi?thread_show=24481 > > That doesn't work for me, so I've got a version here that DOES work as > straight C (I think): > > Credit to Jamie Lokier for the original idea and Chad Austin for the flipcode > > example in C++. I'm posting it here in case I've missed something obvious. > ;-) > > #include <stdio.h> > #define ENUM_BODY(name, value) \ > name = value, > #define AS_STRING_CASE(name, value) \ > case name: return #name; > #define FROM_STRING_CASE(name, value) \ > if (strcmp(str, #name) == 0) { \ > return name; \ > } > #define DEFINE_ENUM(name, list) \ > typedef enum { \ > list(ENUM_BODY) \ > }name; \ > const char* asString(name n) { \ > switch (n) { \ > list(AS_STRING_CASE) \ > default: return ""; \ > } \ > } \ > name fromString(const char* str) { \ > list(FROM_STRING_CASE) \ > return 0; /* assert? throw? */ \ > } > #define ENUM_LIST(_) \ > _(RED, 0) \ > _(GREEN, 1) \ > _(BLUE, 87) > > DEFINE_ENUM(Color, ENUM_LIST) > > int main() { > Color c = GREEN; > printf("%d\n",c); > printf("%s\n", asString(c)); > printf("%d\n", fromString("BLUE")); > } > > gcc enum.c > > Output: > > [EMAIL PROTECTED]:~/tmp/enum$ ./a.out > 1 > GREEN > 87 > > I need this functionality to convert potentially any enum already defined in > > GnuCash into a form that is usable AS an enum by all existing processes and > which can be converted to a const char* on demand, with only one piece of new > > code, no duplication and as efficiently as possible. Only enums that are used > > as QOF parameters (presently gint32/gint64) would actually take this new > form. The parameter would then be changed to QOF_TYPE_STRING and a function > defined. That would get the enum from the existing function (as a wrapper) > and then pass that to asString() above. > > The parsed version of the defines (using gcc -E) shows the expanded section > as: (line breaks added) > > typedef enum { RED = 0, GREEN = 1, BLUE = 87, }Color; > > const char* asString(Color n) { > switch (n) { > case RED: return "RED"; > case GREEN: return "GREEN"; > case BLUE: return "BLUE"; > default: return ""; > } > } > > Color > fromString(const char* str) > { > if (strcmp(str, "RED") == 0) { return RED; } > if (strcmp(str, "GREEN") == 0) { return GREEN; } > if (strcmp(str, "BLUE") == 0) { return BLUE; } > return 0; > } > > int main() { > Color c = GREEN; > printf("%d\n",c); > printf("%s\n", asString(c)); > printf("%d\n", fromString("BLUE")); > } > > Can anyone see problems with this solution? Are the defines correct C? > > Do we want to use safe_strcmp? > Should the strings be translatable? > #define AS_STRING_CASE(name, value) \ > case name: return _(#name); > instead of return #name? > > Comments? Problems? > > -- > > Neil Williams > ============= > http://www.dcglug.org.uk/ > http://www.nosoftwarepatents.com/ > http://sourceforge.net/projects/isbnsearch/ > http://www.neil.williamsleesmill.me.uk/ > http://www.biglumber.com/x/web?qs=0x8801094A28BCB3E3 > > -- Derek Atkins, SB '93 MIT EE, SM '95 MIT Media Laboratory Member, MIT Student Information Processing Board (SIPB) URL: http://web.mit.edu/warlord/ PP-ASEL-IA N1NWH [EMAIL PROTECTED] PGP key available _______________________________________________ gnucash-devel mailing list gnucash-devel@gnucash.org https://lists.gnucash.org/mailman/listinfo/gnucash-devel
