Re: [TCLCORE] TIP #268: Enhance 'package' Version Handling

[Hemang L. <hl...@ci...>]

dg...@ni... wrote:
> Quoting Jeff Hobbs <je...@ac...>:
>   
>>  TIP #268: ENHANCE 'PACKAGE' VERSION HANDLING 
> ...
>
>
> In general, to evaluate any proposal regarding [package]
> one must examine at least the two perspectives of the
> package author (the [package provide] side) and the package
> user (the [package require] side).  Try to establish
> examples of how they will use the proposed feature,
> and whether the new usage patterns are sufficiently
> useful and sufficiently convienient that they will
> actually be welcome.
>   
The main purpose of this proposal is to deliver pre-release software to
the end user for early testing and make this process as simple as
possible. This is achieved as follows:

1. Ask the user to download and install the new package(s) in standard
tcl installation path where scripts can find it. End-user should not
have to remember the path where such a package is installed.

2. Enable the level of threshold via environment variable
TCL_PKG_THRESHOLD to one of "alpha", "beta" or "rc". I don't think
asking end-users to modify their scripts to specify the threshold level
will be an  acceptable solution.

Note that this approach does have a limitation: it does not provide a
finer level of control over which packages to load at a given threshold
level.  If there are two beta packages: foo and bar, it will not be
possible to enable only foo package. If users need such finer control,
they will be recommended to install desired packages under a separate
path in the filesystyem which can be added using TCLLIBPATH and specify
threshold level as "alpha".

For most end-users, I believe that installing under std tcl path and
specifying the threshold level via TCL_PKG_THRESHOLD should suffice.

Hemang.