[PATCH][RFC] Support for keyword expansion

[Eric Bloodworth]

On Mon, 2005-09-19 at 14:05 -0700, Matt Mackall wrote:
> On Tue, Aug 30, 2005 at 09:29:38PM +0200, Goffredo Baroncelli wrote:
> > Hi all,
> > 
> > the patch below is an initial support for a keywords expansion framework. 
> 
> Can you rework this as a generic filter script for contrib/? 
> 
> I'm personally not a believer in keyword expansion - you either a)
> have the repo at hand to query such things directly, making it
> redundant or b) you've gotten a copy of the file without access to the
> repo, in which case the expansions are potentially out of date or more
> often irrelevant, etc. About the only thing they're good for is determining
> whether a hardcopy sitting on your desk should be recycled, for which
> the answer is usually yes anyway.
> 

The only useful application of keyword expansion I've ever seen was when
it was used to embed version information in object code (using static
char *'s).  Assuming builds are done correctly, libraries and
executables can be examined with the "strings" program to identify the
source files used in the build.  

This was with a CVS based system, and a string was embedded in each
file.  With mercurial, the ChangeSet id could be a useful expansion for
each executable, but since hg can be used to generate that information,
keyword expansion would just be a convenience. 


-- Eric