On 4/15/12 Apr 15 -3:46 PM, Daniel Herring wrote: ....
One proposal was to use a special sequence at the start of the file, like Emacs or other tools use for specifying configuration settings. However, this needs to then be compatible with those tools. This implies that ASDF needs to know a wide variety of such formats or has to introduce a sufficiently unique format to coexist with others.
I disagree. Since way back in the 1970s the mode line format that emacs uses has been standard in this community. It would be fine to use that. If people with alternative tools want to provide extensions to handle different specification techniques, that's fine, and we could incorporate them. But using the mode line should be acceptable; we don't need to overthink this.
What if ASDF allowed one ASD file to set up a dynamic scope when including another ASD file? I think this might also clean up some places where people are currently invoking CLOS.
I think that suggestion won't work for a couple of reasons:
1. As Faré points out, it's not the person who loads the system who knows what the charset should be, it's the author of that system. So it's wrong to use this kind of mechanism to allow the loader to control the charset of someone else's code: we need to allow the AUTHOR (rather than the loader) of the system to specify the charset.
2. It's not at all clear what that dynamic scoping would mean. Remember that the defsystem is not necessarily parsed inside the loading, and that there is the whole confounding issue of the construction and then execution of the operation plan.