On Tue, Aug 16, 2016 at 5:49 PM, Robert P. J. Day <rpj...@crashcourse.ca> wrote: > On Tue, 16 Aug 2016, Ulf Magnusson wrote: > >> On Tue, Aug 16, 2016 at 4:02 PM, Robert P. J. Day <rpj...@crashcourse.ca> >> wrote: >> > >> > was about to submit a small number of patches to clean up redundancy >> > when people combine "_append" with "+=" (because it offends my >> > delicate sensibilities), and ran across this in oe-core, >> > unfs3_0.9.22.r497.bb: >> > >> > DEPENDS_append_class-nativesdk += "flex-nativesdk" >> > >> > uh, what? >> > >> > most of the time, i assume the above doesn't hurt, it's just ... >> > silly. but normally, with "_append", you *need* to add the leading >> > space explicitly, and that's not being done above. so does that mean >> > that combining "_append" with "+=" *does* generate a leading space? >> > that just makes my head hurt -- the possibility that "_append" is >> > being used in a way that normally makes it fail, only to have "+=" >> > step in and save the day. at which point "_append" saves processing >> > that until the end of parsing? yeesh. >> > >> > thoughts? >> >> By the point the += is handled, the override won't have been interpreted >> yet. My guess is that += fetches the value of the variable >> "DEPENDS_append_class-nativesdk", gets back the empty string, and >> adds a space followed by "flex-nativesdk" to that. >> >> The resulting " flex-nativesdk" is then interpreted as usual when the >> overrides are handled. >> >> You might like the note I added to >> https://www.yoctoproject.org/docs/2.2/bitbake-user-manual/bitbake-user-manual.html#override-style-operation-advantages >> by the way. :) > > that note is pretty much what i've been whining about for a long > time. :-) in any event, when one sees something like the above:
The intent of the note was to discourage use of '+=' together with _append, because it's redundant and potentially confusing. Do you think it fails (even in context)? :/ > > DEPENDS_append_class-nativesdk += "flex-nativesdk" > > what is the *proper* cleanup? I'd say the following: DEPENDS_append_class-nativesdk = " flex-nativesdk" Cheers, Ulf -- _______________________________________________ Openembedded-core mailing list Openembedded-core@lists.openembedded.org http://lists.openembedded.org/mailman/listinfo/openembedded-core
