[Xapian-discuss] TCL -> Xapian bindings problem?

[Michael Schlenker]

Olly Betts wrote:

> On Thu, Oct 21, 2004 at 10:02:30PM +0200, Michael Schlenker wrote:
> 
>>(A call to Tcl_PkgProvide must be inside the Swig generated binding if 
>>there isn't a SWIG option to just set the version).
> 
> 
> Actually, there is:
> 
> swig -pkgversion 0.8.3 [...]
> 
> The code in CVS now sets this, creates pkgIndex.tcl and installs stuff
> in a xapian0.8.3 subdirectory of the tcl library directory (which seems
> to be the convention from looking at what other packages do).

Typical convention for Tcl packages not bundled with core Tcl (bundled 
with core tcl are msgcat, http, registry, dde), is to install them in a 
subdir of $auto_path, the package search path, usually /usr/lib, but 
putting them in the Tcl dir (for example /usr/lib/tcl8.4/xapian0.8.3) 
works also.

The reason for this is simple, for Tcl you _do not_ have to recompile an 
extension just to use a newer core Tcl version, if it uses the TCL_STUBS 
interface (i don't know if swig sets this automatically, but it could 
be). This means if you can compile xapian against a Tcl 8.1 and have the 
package it loads into Tcl 8.1, 8.2, 8.3, 8.4 and will load into the 
upcoming 8.5 (about six years of binary compatibility). So stubbed 
packages residing in /usr/lib can be found and used by all installed Tcl 
versions, while packages put under /usr/lib/tcl8.4/packagename are just 
not seen by the package mechanism of a Tcl 8.3.

Michael