On Thu, May 23, 2013 at 11:30 AM, atkaaz <atk...@gmail.com> wrote: > So all I was saying above is that it should throw when [] is empty just as > it does when [] is not empty, but it doesn't throw when empty because it's > never called (by "it" i mean "false" not "false?") >
This sort of behavior is handy for users new to the language but generally goes against the grain in a dynamic language (e.g., Clojure, Ruby, Python, JavaScript). If you want libraries to consistently error when you try to pass the wrong sort of thing to a method or function, there are a whole bunch of languages that make it inconvenient not to do that (e.g., Haskell, Scala, Java, Go). In a dynamic language this requires extra code in every method or function that makes assumptions about its arguments' types. People who choose dynamic languages often do so in part because of how little code it takes to do powerful things. So I think the communities largely see validation of arguments as clutter. That doesn't mean it's never done, but it's kept to a minimum. For example, clojure supports adding :pre and :post conditions to a fn's metadata, but that feature seems to be used only three times in clojure itself: twice in clojure.reflect.java and once in clojure.uuid. On the other hand, many macros in clojure.core validate their usage with the private assert-args. This philosophical bent also comes up in question about how to design a library so that users can't mess up certain things. In the Java community, that's a common concern. In Clojure-land, the prevailing wisdom is to design and document so that it's easy to do the right thing but not worry much about people who do the wrong thing. -- -- 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.
