Re: Multiple rules for same target: what is the order of prerequisites in $^ and what does $< expand to?

[Bahman Movaqar]

On Mon, 2023-10-02 at 14:56 -0400, Paul Smith wrote:
> On Mon, 2023-10-02 at 11:48 -0700, Bahman Movaqar wrote:
> > my-target : foo
> > my-target :
> >         @echo 'my-target: $$(<) is $(<)'
> 
> This is an unusual way to construct this rule.  Normally it would be:
> 
>   my-target : foo
>             @echo 'my-target: $$< is $<'
> 
> whereupon the value of $< is reliably "foo" regardless of anything else
> in the makefile.

Thanks for the hint re style.  Finding good examples of writing easy-to-
read make files is no easy feat.  That's why I do have these inaccuracies
in my personal style.

> 
> > That brings me to the natural question:  why would anyone ever use
> > `$(<)'?  In other words, what is an appropriate usecase for that
> > variable?
> 
> You have to use automatic variables, including $<, when you write
> implicit rules.  There is no other option.

That makes sense.  Thanks.

-- 
Bahman

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