It is probably instructive to look at how (use-primitive-operators) works in primitive-math [1], though maybe not something you want to emulate. The basic mechanism is pretty simple: use 'ns-unmap' to get rid of the operators you want to shadow, and bring in the operators from the alternate namespace.
Unfortunately, the next time you load the namespace, you'll get the same mess of collision warnings you were trying to avoid, because you haven't added the ':refer-clojure :exclude' clause to the ns declaration. To get around this, use-primitive-operator hijacks 'ns' via alter-var-root so that this is automatically added if the alternate operators are detected [2], but otherwise leaves it unchanged. This hijacking is undone if clojure.core is ever reloaded (usually by a :reload-all somewhere), however. This could be fixed by adding a watcher to #'clojure.core/ns and forcing it back whenever it changes, but I haven't done that yet because it doesn't really affect me, and it feels hokey enough already. Despite all that, though, it works pretty well. Feel free to use this approach if you like, or create a less questionable variant if you can think of one. Zach [1] https://github.com/ztellman/primitive-math/blob/master/src/primitive_math.clj#L154 [2] https://github.com/ztellman/primitive-math/blob/master/src/primitive_math.clj#L135 On Wednesday, September 4, 2013 6:22:08 PM UTC-7, Mikera wrote: > > Hi all, > > While building the API for core.matrix, I've fun into a few cases where > the "best" name is a direct clash with clojure.core. > > Examples are "+", "zero?", "vector?", "==" > > In many of these cases, the core.matrix behaviour is a natural extension > of the clojure.core function (i.e. it extends the same functionality to > arbitrary N-dimensional arrays). > > I'm not very happy with any of the options I can see for handling this: > > A) Use the good names in the "clojure.core.matrix" namespace. Problem: > that gives you a ton of nasty warnings of the type "WARNING: + already > refers to: #'clojure.core/+ in namespace: test.blank, being replaced by: > #'clojure.core.matrix/+". Significant boilerplate must be maintained by the > user in their ns declaration to prevent these warnings. I don't like > forcing users to maintain boilerplate, and I think that normal idiomatic > usage should be warning-free. > > B) Separate the name-clashing functions into separate namespaces - e.g. > "clojure.core.matrix.operators". Problem: that's something of an artificial > division, and again it forces users to do extra ns-management work to > access the functions they want. > > C) Use different names. Problem: names would be worse, and this would be > inconsistent and confusing, especially for functions that do effectively > the same thing. > > D) Encourage users to use aliases. Problem: that's horrendously ugly and > inconvenient for numerical code. Users with any sense of elegance in their > coding style would quite rightly throw their hands up in disgust. > > Currently we're doing B), I'd prefer to do A) but can't figure out a way > to automatically suppress the warnings. > > Any better ideas? > > > > -- -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
