Re: How to define rule of rules?

[Peng Yu]

On Sat, May 1, 2010 at 5:52 PM, Stephan Beal <address@hidden> wrote:
> On Sun, May 2, 2010 at 12:08 AM, Peng Yu <address@hidden> wrote:
>>
>> I need to define many rules like RData_rule, png_rule, csv_rule, ....
>>
>> Is there a way to define a macro that can define these rules (with the
>> parameter like RData and png)?
>
> You're looking for $(call). Here's an example, taken from a makefile i've
> got laying around:
> ########################################################################
> # ShakeNMake.EVAL.RULES.BIN is intended to be called like so:
> # $(eval $(call ShakeNMake.EVAL.RULES.BIN,MyApp))
> #
> # It builds a binary named $(1) by running $(CXX) and passing it:
> #
> # LDFLAGS, $(1).BIN.LDFLAGS
> # $(1).BIN.OBJECTS
> define ShakeNMake.EVAL.RULES.BIN
> $(1).BIN = $(1)$(ShakeNMake.EXTENSIONS.EXE)
> $(1).BIN: $$($(1).BIN)
> # Many developers feel that bins should not be cleaned by 'make
> # clean', but instead by distclean, but i'm not one of those
> # developers. i subscribe more to the school of thought that distclean
> # is for cleaning up configure-created files. That said, shake-n-make
> # isn't designed to use a configure-like process, so that is probably
> # moot here and we probably (maybe?) should clean up bins only in
> # distclean. As always: hack it to suit your preference:
> CLEAN_FILES += $$($(1).BIN)
> $$($(1).BIN): $$($(1).BIN.OBJECTS)
>        address@hidden x = "x$$($(1).BIN.OBJECTS)" && { \
>         echo "$(1).BIN.OBJECTS is undefined!"; exit 1; }; \
>         $(call ShakeNMake.CALL.SETX,"CXX address@hidden ..."); \
>         $$(CXX) -o $$@ \
>                 $$(CXXFLAGS) $$($(1).BIN.CXXFLAGS) \
>                 $$($(1).BIN.OBJECTS) \
>                 $$(LDFLAGS) $$($(1).BIN.LDFLAGS)
> # note about 'set -x': i do this because it normalizes backslashed
> # newline, extra spaces, and other oddities of formatting.
> endef
> ########################################################################

I don't understand the above code. Would you give me the minimal code
for the scenario that mentioned in my first email?

-- 
Regards,
Peng