[PATCH] Add keyword aliases during substitution

Hi,

Since I've transferred most of my local development to Subversion
repositores in the past year or so, there is only one thing that
I've missed from the CVS days - the ability to use a different
keyword to represent the Id tag, a keyword that is specific to
my repository, so it does not interfere with vendor-imported code
and such. Examples of these may be found as the $FreeBSD$ tag in
the FreeBSD.org repository, the $XFree86$ tag in the, well, XFree86
development, and so on :)

I wonder if the following patch will be enough - I haven't played with
Subversion too deeply, especially with its language bindings... maybe
some changes will be needed there, too. Also, this might kinda break
any code that still uses svn_subst_build_keywords() - I can't seem to
think of a way to represent aliased keywords in the old-style structure :(

Still, what do you think of this idea?

[[[
Enhance keyword substition: allow keyword aliases.

Enhance keyword substition: allow keyword aliases, defined as new=old in
the svn:keywords property. Thus, if svn:keywords contains Ringlet=Id,
$Ringlet$ would be expanded as $Id$, while $Id$ would be left untouched.
Of course, if svn:keywords contains both Id and Ringlet=Id, both keywords
would be expanded.

Note that aliases may only be defined for "original" keywords; thus,
"Ringlet=Id More=Ringlet" would not expand $More$ at all.
]]]

G'luck,
Peter

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Peter Pentchev	roam@ringlet.net    roam@cnsys.bg    roam@FreeBSD.org
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If this sentence were in Chinese, it would say something else.