-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 According to Vincent Torri on 11/10/2008 12:47 AM: Hello Vincent, > I want to write a generic macro that check if different image library > (libjpeg, libpng, etc...) are available. > Is it possible to achieve what I want ? Yes, it is possible. > dnl use: EVAS_CHECK_IMAGE_LOADER(loader, want_loader) > AC_DEFUN([EVAS_CHECK_IMAGE_LOADER], > [ > > pushdef([UP], translit([$1], [a-z], [A-Z]))dnl Please use m4sugar names; while autoconf currently re-exports raw m4 names, this may trigger a warning in the future (as it is not namespace clean). So this should be m4_pushdef, not pushdef. > pushdef([DOWN], translit([$1], [A-Z], [a-z]))dnl Underquoted - translit does not output its argument with quotes, so if $1 happens to match a macro name, it will be re-expanded. Also, you may want to consider using m4_toupper/m4_tolower instead of directly calling translit. As in: pushdef([UP], m4_toupper([[$1]], [a-z], [A-Z])) > > have_evas_image_loader_[]DOWN="no" > > EVAS_CHECK_LOADER_DEP_[]UP( Here's your problem. You are outputting the literal string EVAS_CHECK_LOADER_DEP_ (which is not defined as a macro), then outputting the expansion of UP(args) (which is also not defined as a macro). What you really need is another layer of expansion that pastes together the two strings, and expands the pasted result as a single macro name. There are several possibilities, pick the one you think looks nicest (and recalling that some of these macros weren't available/documented in older autoconf versions): m4_unquote(m4_join([], [EVAS_CHECK_LOADER_DEP_], m4_defn([UP])))(args) m4_default([], [EVAS_CHECK_LOADER_DEP_]m4_defn([UP]))(args) > [DOWN], Possibly overquoted. You need to decide whether you want to pass the lower-case name as the argument, rather than the name of a macro that expands to the lower-case name (it depends on whether EVAS_CHECK_LOADER_DEP_* use their $1 as a literal string in investigating further macro names, or whether waiting until after the child macro is expanded before converting to lower-case is acceptable). > [have_evas_image_loader_[]DOWN="yes"], > [have_evas_image_loader_[]DOWN="no"]) > > popdef([UP]) > popdef([DOWN]) Again, use m4_popdef. And in newer autoconf, it is more efficient to pop two definitions at once: m4_popdef([UP], [DOWN]) - -- Don't work too hard, make some time for fun as well! Eric Blake ebb9@xxxxxxx -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (Cygwin) Comment: Public key at home.comcast.net/~ericblake/eblake.gpg Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEARECAAYFAkkYNKIACgkQ84KuGfSFAYC/tQCfbgu7Fmk+b/KHrfNEn1lBUbwh L6kAn1uyyUyGxASV/md2zTqSWbj+nGtV =qgI9 -----END PGP SIGNATURE----- _______________________________________________ Autoconf mailing list Autoconf@xxxxxxx http://lists.gnu.org/mailman/listinfo/autoconf
