Some simple ideas for the new system

From: david.abrahams_at_[hidden]
Date: 2001-11-22 10:30:06

I always thought it would make sense to have some notion of 
"inheritable" target properties, such that you could set the 
properties for a main target (e.g. an exe), and its intermediate 
dependencies (e.g. object files) would automatically inherit those 
properties. Even if we don't choose to do that, there is a lot of 
information currently being associated with each target, for 
example, where it will be located in the filesystem: 
$(gLOCATE($(target)), and what needs to be in the PATH in order to 
run it or targets dependent on it: $(gRUN_PATH($(target)).

We could use the module system to store this sort of information as 
local variables of an "internal" module (meaning one that's not part 
of a file loaded with "import") whose name is derived from the 
target name. If dependencies are established through some bottleneck 
rule (rather than the built-in DEPENDS), we can record the 
dependency graph information and implement the property inheritance.

-Dave