I look at side effects this way, will it ever record some state change that some code in the universe will eventually rely on ?
If no, then there's no state change/side effect to care about. Sending a message is a side effect (a pgm will eventually use it), writing to a database, ... qualify. Changing a screen output which has no long term memory of what is written to it and is meant to communicate with carbon entities is not to me a side effect. A GUI to me is merely a way to present some state information, not a state by itself. It can always be constructed back again. So unless we evolve to some silicon dice life form, this rule helps me segregate what is a side effect from a code standpoint :) That may help, Luc P. > 2014-07-10 19:10 GMT+02:00 Softaddicts <lprefonta...@softaddicts.ca>: > > > The fn that does the display is the one having side effects. > > Now if your look fn creates the side effect, it should reflect that in its > > name. > > > > Look discribes the current location. So it has a side-effect, but as I > understood from others it is not about side-effects, but global state. That > does not change, so I should not use the '!'. > > > > > > But... I wonder why it does so. Looking at something does not change state. > > > > No, it does not change state, but it prints the description. So it has a > side effect. It is not pure, but it is idempotent. > > -- > Cecil Westerhof > > -- > 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/d/optout. > -- Softaddicts<lprefonta...@softaddicts.ca> sent by ibisMail from my ipad! -- 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/d/optout.
