Paul Mensonides a écrit :
Hi Loïc.
Okay, I have a little more time now.
Thank you for your help, it helps me clarify some fuzzy points.
I'm trying to use the boost preprocessor library to allow the user to define "rich" enums, for instance enums that cannot be converted to int, whose values can be displayed in human readable form on a stream...
You might already know that there are several fancy enum implementations around. However, I'm not sure if any them fit what you're looking for. Specifically, enumerators that cannot be converted to integers. What you want, AFAICT, is a set of symbols only that share a common type. You may want to look for existing implementations first.
I do this for a personnal project, part of which is to improve my skills, so even if I crave for re-use, not this time. By the way, I had a little check, and no fancy enum I have seen seems to have reached a wide acceptance yet, or to cover my requirements. Maybe I will call my system yafe (yet another fancy enum) :). [snip example]
In other words, the importance of debuggability greatly depends on what you're generating--i.e. what you want the preprocessor to write for you. If it is something complex, particularly if it can fail inside the specific generated code, then debuggability is more important.
And now, the questions : Which writing do you think would be best ? Why ? Are there other possibilities I overlooked ? Is is possible to have a syntax like 1/ and 2/ with good debugability ?
To the last, yes. But the point at which it is debugged is different. Instead, when you write something like the above, you debug the preprocessor metaprogram to make sure it is generating what you want, and then you debug the *pattern* that it is generating by creating instances of the pattern (like color above), and making sure that it works correctly. Once that is done, you shouldn't have to debug it again.
Ok, I think I can see your point. I guess that my reluctance was due to the fact that since I am not fluent in cpp, I was afraid to create a macro that would span on many lines. Let's go for this syntax then. Maybe I will publish the result in the mailing list files area, if I think "yafe" can be of interrest to other people. Regards, -- Loïc