Re: [Boost-build] make rule with extra variables + figuring out the full target path

Subject: Re: [Boost-build] make rule with extra variables + figuring out the full target path
From: Vladimir Prus (ghost_at_[hidden])
Date: 2010-02-10 15:50:32

On Wednesday 10 February 2010 22:32:59 Fadi Beyrouti wrote:

> 
> > > 
> > > 1. Is there a way to get that path?
> > > 2. Is there a better/cleaner way of doing what I want to do?
> > 
> > Does it work if you add
> > 
> > 	constant EXTRA_VAR : SOME_VALUE ;
> > 
> > somewhere in your Jamfile? In fact, even
> > 
> > 	EXTRA_VAR = SOME_VALUE ;
> > 
> > will work, but 'constant' are inherited by child Jamfiles, so is better.
> 
> 
> 
> Thanks Volodya for the clarifications.
> 
> 
> This actually works only partially. The reason is that I am actually inside a
> for loop
> 
> for local TARGET in $(TARGETS)
> {
>     make $(TARGET).myext : 
>          my_source_file : 
>          @my_action :
>          <location>"dir1/dir2/dir3" ;
> 
>     constant EXTRA_VAR : $(TARGET) ;
> }
> 
> unfortunately $(EXTRA_VAR) always takes the value of the last element of the
> list of $(TARGETS). This is kind of why I use the "on" construct. Is there any
> way of getting that target passed to the action?

Oh, your original email did not mention the loop. Try this:

import feature ;
import toolset ;

feature.feature whatever : : free ;
toolset.flags my_action EXTRA_VAR : <whatever> ;

and then use <whatever>$(TARGET) as extra requirement when defining a 'make' metatarget.

- Volodya