Akim Demaille wrote:
> Le 21 sept. 2012 à 16:44, Jim Meyering a écrit :
>
> Hi!
>
>>> diff --git a/top/maint.mk b/top/maint.mk
>>> index 87bbde9..e8ea768 100644
>>> --- a/top/maint.mk
>>> +++ b/top/maint.mk
>>> @@ -91,13 +91,22 @@ my_distdir = $(PACKAGE)-$(VERSION)
>>> # Old releases are stored here.
>>> release_archive_dir ?= ../release
>>>
>>> +# Validate and return $(RELEASE_TYPE), or die.
>>> +GET_RELEASE_TYPE = \
>>> + $(if $(RELEASE_TYPE), \
>>> + $(or $(shell case '$(RELEASE_TYPE)' in \
>>> + (alpha|beta|stable) echo $(RELEASE_TYPE);; \
>>> + esac), \
>>> + $(error invalid RELEASE_TYPE: $(RELEASE_TYPE))), \
>>> + $(error RELEASE_TYPE undefined))
>>
>> This looks like a fine improvement.
>> However, can't you do it without the cost of a $(shell ...)?
>> How about using $(findstring ...) instead?
>> Would be nice, but not required.
>
> I tried to do it in pure GNU Make, but I couldn't find a
> means to do it. For instance findstring finds alpha in
> alphabet. Could find a means to use filter or filter-out
> either to make sure there is just one string, and one
> I want.
How about something like this?
release-type = \
$(subst :, , \
$(if $(RELEASE_TYPE), \
$(or $(findstring :$(RELEASE_TYPE):,:alpha:beta:stable:), \
$(error invalid RELEASE_TYPE: $(RELEASE_TYPE))), \
$(error RELEASE_TYPE undefined)))
That's not quite right because it fails to reject RELEASE_TYPE=alpha:beta.
Adding one more "if" just for that case should do the job:
release-type = \
$(subst :, , \
$(if $(RELEASE_TYPE), \
$(if $(findstring :,$(RELEASE_TYPE)), \
$(error invalid RELEASE_TYPE: $(RELEASE_TYPE)), \
$(or $(findstring :$(RELEASE_TYPE):,:alpha:beta:stable:), \
$(error invalid RELEASE_TYPE: $(RELEASE_TYPE)))), \
$(error RELEASE_TYPE undefined)))
> I find it surprising that there is nothing available to
> compare strings (but ifeq etc. which does not apply here:
> I want the code to be run when the variable is read, not
> when it is defined).
...
Yeah, GNU make functions do take some getting used to.
