How can I determine if a function is available?

[Ryan Schmidt]

On Apr 13, 2007, at 08:49, Daniel J. Luke wrote:

> On Apr 12, 2007, at 10:37 PM, Boey Maun Suang wrote:
>
>> As far as I can tell, however, work on base to allow for executing  
>> ${build} in multiple directories would probably be necessary to  
>> deal with curlhandle and nefu, as well as with the dovecot-sieve  
>> plugin that I've been trying to write a port for.  I haven't  
>> looked at the other two, but the dovecot-sieve source has been  
>> written on the premise that it will be extracted in a directory  
>> _adjacent_ to the main dovecot sources (i.e. ${blah}/dovecot-$ 
>> {version} and ${blah}/dovecot-sieve-${version}), _and_ that that  
>> it will be build against the main dovecot sources _in the places  
>> in which the object files will be emitted by default in the  
>> dovecot build directory_.  It seems like an awful lot of hacking  
>> on the Makefiles (which I'm not comfortable about doing just yet)  
>> would be needed to get dovecot-sieve to work without using  
>> [command build], either as a variant or as a separate port.
>
> Instead of [command build] you could do what the build command  
> would be doing...
>
> ie, system "cd whatever/ && make"
>
> It's not ideal (and probably base/ should be enhanced to have hooks  
> so you don't have to do that sort of thing), but it doesn't involve  
> using internal API.

How would such hooks differ from the private API that's already in  
place? Since the private API already seems to work, adding a public  
wrapper around it should be very easy, shouldn't it?