Re: [Boost-build] How to get Boost build to embed install path into library

From: Jonathan Biggar (jon_at_[hidden])
Date: 2008-07-24 00:10:07

Jonathan Biggar wrote:
>>   My suggestion is to define a new composite, non-incidental feature.
>>
>>   However this is not supported for 'free' features that take 'any 
>> text' as their value (because Boost Build currently encodes used 
>> properties that affect the build as path to the built target and free 
>> feature values would mess up that path). You would need to define a 
>> list of possible tag values and then convert them to exact paths 
>> inside your build script.
> 
> The last part is a problem, since the idea is to allow the user to build 
> the library and install it wherever he likes, which isn't compatible 
> with a preset list of feature values.
> 
> But I wonder if it's possible to declare the feature and then use 
> feature.extend to add the value I need on the fly (derived by converting 
> '/' to '-' from the user provided install path).  Or even simpler, just 
> calculate the right value up front before declaring the feature.
> 
> I'll have to experiment and see if I can make that work.

Yup, that worked like a charm.  I did something like this:

install-path = /foo/bar ;

embedded-path =
     [ string.join [ string.words $(install-path) : / ] : % ] ;

feature.feature embedded-paths : no-paths $(embedded-path) : implicit;

lib foo
     : $(SOURCES)
     : <embedded-path>$(embedded-path) <define>MYPATH=$(install-path)
     ;

package.install
     :
     : foo
     :
     : <install-default-prefix>$(install-path)
     ;

and foo%bar shows up in my build directory path, which ensures that the 
library gets installed with the same embedded path it was built with.

-- 
Jon Biggar
Floorboard Software
jon_at_[hidden]
jon_at_[hidden]