NO_BUILD handling

[Brook Milligan <brook%nmsu.edu@localhost>]

Will someone please explain the rationale for the NO_BUILD mechanism being based upon defined/undefined rather than definitions of yes/no?

I am asking because I have a LaTeX package that needs to run latex on a *.ins file in order to generate the *.sty file prior to installing.  However, the texlive/package.mk file (conditionally) defines the NO_BUILD make variable, so no *-build targets (the logical place to put the latex command) get run.  If the mechanism was based upon the value defined, i.e., yes/no, then this package could override the default and work.

As a matter of context, there are no instances in the tree definitions of NO_BUILD that are not of the form "NO_BUILD=yes" (case for yes varies).  There are only three module.mk files with conditionals based upon NO_BUILD and those all seem able to handle either undefined values or values set to yes/no.  

Thus, as a practical matter it seems that the bit in mk/build/bsd.build.mk that implements the NO_BUILD handling could be changed to handle yes/no instead of defined/undefined and there would be no impact on existing packages.

Perhaps there is logic that I am missing, however, so I would appreciate an explanation from those more knowledgable than myself.

Thanks.

Cheers,
Brook