Re: bogus restriction

From: David Abrahams (dave_at_[hidden])
Date: 2005-02-11 11:14:50

Vladimir Prus <ghost_at_[hidden]> writes:

> On Wednesday 09 February 2005 19:23, David Abrahams wrote:
>
>> If the tool's version can be specified during initialization, make
>> sure the version is either always specified, or never specified (in
>> which case the tool is initialied only once). For example, if you
>> allow:
>>
>> using yfc ;
>> using yfc : 3.3 ;
>> using yfc : 3.4 ;
>>
>> Then it's not clear if the first initialization corresponds to
>> version 3.3 of the tool, version 3.4 of the tool, or some other
>> version. This can lead to building twice with the same version.
>>
>>
>> In my opinion that would not be so terrible, and would be much less harmful
>> than this restriction is. Currently if I'm a site administrator I
>> can't write
>>
>> using gcc ;
>>
>> for my average user if I think some advanced user may need
>>
>> using gcc : 3.3 ;
>>
>> in his site-config.
>>
>> Much better would be to allow the versionless toolset to exist
>> alongside the versioned one (possibly issuing a warning), 
>
> What if I have 
>
> using gcc ;
> using gcc : 3.3 ;
>
> and run 
>
> bjam gcc
> bjam gcc-3.3
>
> will the same target directory be used in both cases? Or different ones? In 
> other words, will the default version of gcc be "unspecified" or "3.3"?

Well, considering the additional options:

0. Nothing more

or

1. provide a way for users to un-configure the versionless toolset

or

2. have the toolset automatically un-configure a versionless toolset
if the user ever specifies a version number.

In case 0 they will use different directories.

case 1 is just like case 0 unless they un-configure gcc, in which case
it's just like case 2.

In case 2 they use the same directory.

-- 
Dave Abrahams
Boost Consulting
www.boost-consulting.com