Re: [jamboost] describing template targets in Jamrules

From: Toon Knapen (toon.knapen_at_[hidden])
Date: 2004-04-27 03:51:57

Rene Rivera wrote:

> Toon Knapen wrote:
> 
>>Is it possible to describe template targets in the Jamrules in bjam.v1. 
>>I tried but it does not seem to work. 
> 
> 
> Not really. Since template are real targets they can only be in 
> Jamfiles. Of course it's always possible to kludge something, but it 
> probably not worth it.
> 

No it is not worth it. Including one file defining the templates in all 
other files works fine too.

> 
>>So now I
>>
>>include $(PROJECT_ROOT)/template_target_desciptions ;
>>
>>in the Jamfile of some subprojects. But the documentation says that the 
>>template definition is relative to the subdirectory of the Jamfile 
>>containing the template definition. Is that $(PROJECT_ROOT) in my case 
>>or the location of the Jamfile of my subproject ?
> 
> 
> Tricky question to answer, with the limited information.... The basic 
> rule is that the template targets are defined in the Jamfile that 
> includes the template_target_descriptions. So if you are referring to 
> them in the same Jamfile you just use the base target name. If you are 
> in another subproject you need to use a relative path to the template 
> targets. And if you include the file from multiple Jamfiles you'll end 
> up with many versions of the template same template targets. For example:
> 
> root/template_target_descriptions (ex. declares a "app" template)
> root/sub1/Jamfile (includes the templates)
> root/sub2/Jamfile
> root/sub3/Jamfile (includes the templates)
> 
> You'll end up with these template targets: @root/sub1/app, and 
> @root/sub3/app. "<template>app" in sub1 would refer to the one in sub1 
> subproject, but you could also refer to the one in the sub3 project with 
> "<template>../sub3/app". And in sub2 you can only refer to the templates 
> with a relative path "<template>../sub1/app" and "<template>../sub3/app".
> 
> You could also you the "@_project_/.." syntax to refer to the targets 
> "absolutely".

Thanks for this response. This clarifies things a lot.

toon