convore.json/groups/arc-runtime-project/referring-to-different-versions-of-libraries-in-a-use-form/messages.json

[{"user_id": 25438, "stars": [], "topic_id": 39118, "date_created": 1307905196.176878, "message": "(use arc3.1!srv)\n\n(use awwx!srv)\n\n(use thrush!srv)\n", "group_id": 9739, "id": 1375108}, {"user_id": 25438, "stars": [], "topic_id": 39118, "date_created": 1307905345.67098, "message": "I think \"/\" would be nicer (\"arc3.1/srv\"), but the problem with that is that it conflicts with being able to load code from subdirectories, so I imagine it would turn out to be frustrating.", "group_id": 9739, "id": 1375117}, {"user_id": 25438, "stars": [], "topic_id": 39118, "date_created": 1307905768.0840819, "message": "ok, let's say I have a location such as \"git://github.com/awwx/lib.git\".  If I wanted to load just one thing from that location one time, I could just specify that one file:", "group_id": 9739, "id": 1375152}, {"user_id": 25438, "stars": [], "topic_id": 39118, "date_created": 1307905820.954823, "message": "\n(use git://github.com/awwx/lib.git:between)\n", "group_id": 9739, "id": 1375161}, {"user_id": 25438, "stars": [], "topic_id": 39118, "date_created": 1307905189.3937509, "message": "If I want to use \"srv\", I might want to use the original srv that came with Arc 3.1, or my version, or someone else's version.  Assuming for the moment that I have in some way specified where to find the various versions, what would be the most convenient syntax for referring to a particular version?  One option would be to use \"!\":", "group_id": 9739, "id": 1375107}, {"user_id": 25438, "stars": [], "topic_id": 39118, "date_created": 1307905599.59253, "message": "on the other hand... suppose I could give a location whatever name I wanted for myself.  That is, I could call the Arc 3.1 library location \"arc3.1\" if I wanted, or I could call it \"arc\" if I preferred, or something else.  Then I could avoid conflicting with subdirectories I wanted to use by avoiding giving a location the same name.", "group_id": 9739, "id": 1375136}, {"user_id": 25438, "stars": [], "topic_id": 39118, "date_created": 1307905967.237448, "message": "or, using some mechanism, I could give that location an abbreviation such as \"awwx\".  Then I could say,", "group_id": 9739, "id": 1375171}, {"user_id": 25438, "stars": [], "topic_id": 39118, "date_created": 1307907465.498188, "message": "Another question is how best to override a \"use\" specification in a library that I'm using.  For example, suppose that I'm loading some useful program \"news\" which uses \"srv\".  By default, news should load some specific srv that it knows about and works with.  But I might want to have it use some other srv.  In the worst case, I could fork the news repo and change it to use my srv... but that's extreme.  Perhaps I could have some way to specify location overrides, so that when news is about to load \"git://github.com/awwx/arc3.1.git/srv\" I could have it load a different srv instead.", "group_id": 9739, "id": 1375325}, {"user_id": 25438, "stars": [], "topic_id": 39118, "date_created": 1307905985.1115971, "message": "\n(use awwx/between)\n", "group_id": 9739, "id": 1375172}, {"user_id": 25438, "stars": [], "topic_id": 39118, "date_created": 1307906045.344439, "message": "however, if I had some subdirectory \"foo\" that I wanted to load code from, I could still say", "group_id": 9739, "id": 1375176}, {"user_id": 25438, "stars": [], "topic_id": 39118, "date_created": 1307906056.5493851, "message": "\n(use foo/bar)\n", "group_id": 9739, "id": 1375178}, {"user_id": 25438, "stars": [], "topic_id": 39118, "date_created": 1307906074.8552721, "message": "because I wouldn't have made \"foo\" an abbreviation.", "group_id": 9739, "id": 1375181}, {"user_id": 25438, "stars": [], "topic_id": 39118, "date_created": 1307914061.392307, "message": "ok, let me try pushing this to the most extreme conclusion, and see what seems to make sense.", "group_id": 9739, "id": 1376025}, {"user_id": 25438, "stars": [], "topic_id": 39118, "date_created": 1307914834.6051481, "message": "In ar, things are supposed to able to be loaded as libraries, and libraries are supposed to be able to be published on a code site such as github.  \"arc\" is itself a library, so you should be able to decide to load it or not, or to load a different version.  (or, when arc.arc gets split up into more manageable pieces, you should be able to choose which parts to load).  So let's say I write a \"foo.arc\" that needs arc, so let's say it specifies which arc it knows it works with:", "group_id": 9739, "id": 1376048}, {"user_id": 25438, "stars": [], "topic_id": 39118, "date_created": 1307938733.403394, "message": "(use (= git://github.com/awwx/arc3.1.git/ /home/fred/stuff/))\n(use foo)", "group_id": 9739, "id": 1377199}, {"user_id": 25438, "stars": [], "topic_id": 39118, "date_created": 1307938743.2240579, "message": "Now in the foo.arc use form \"git://github.com/awwx/arc3.1.git/\" would be renamed to \"/home/fred/stuff/\", and the (use foo) would refer to the arc in /home/fred/stuff/arc.arc", "group_id": 9739, "id": 1377200}, {"user_id": 25438, "stars": [], "topic_id": 39118, "date_created": 1307938671.427119, "message": "(use git://github.com/awwx/arc3.1.git/ arc)\n\n(prn \"hi there\")", "group_id": 9739, "id": 1377193}, {"user_id": 25438, "stars": [], "topic_id": 39118, "date_created": 1307938683.6970999, "message": "Now someone else comes along, let's call him Fred. Fred wants to use foo, but he has his own version of arc that he's using. Let's say he has his code in \"/home/fred/stuff\". Thus some program he writes might look like", "group_id": 9739, "id": 1377194}, {"user_id": 25438, "stars": [], "topic_id": 39118, "date_created": 1307938700.413883, "message": "(use /home/fred/stuff/ arc)", "group_id": 9739, "id": 1377196}, {"user_id": 25438, "stars": [], "topic_id": 39118, "date_created": 1307938714.987675, "message": "Fred is always in control. He can look at foo and see what exactly is in there, and he can choose whatever is the most recent revision of foo or he can choose to use a specific revision. He call load foo just as it is, or fork it and change it in whatever way he wants, or he can load foo in an environment which makes it do what he wants instead of what it does by default. In this case he wants the \"arc\" used by foo to refer to his arc instead of the arc3.1.git arc.", "group_id": 9739, "id": 1377197}, {"user_id": 25438, "stars": [], "topic_id": 39118, "date_created": 1307938724.9692841, "message": "Not sure of what the best syntax would be, but suppose Fred can specify abbreviations or renamings so that \"git://github.com/awwx/arc3.1.git/\" would refer to what he wanted.", "group_id": 9739, "id": 1377198}]