Clojurians Log v2

(if @show? "show" "hide") right?

Ah yeah maybe. The important bit is the returned function and the atom outside of that

anyone got experience with implementing https://en.wikipedia.org/wiki/Financial_Information_eXchange clients? are there resources in clj/java that can help one to get started?

is there any documentation that describes what the various metadata flags do? I realise it's extensible but I can't find anywhere that lists the "built-in" ones. specifically ^:redef

Simple question here. I do this a lot: (if a a ...)

let [a (some-calc x y)
     a (if a a (some-alternative x y)]

(or a (some-alternative x y))

event better (or (some-calc x y) (some-alternative x y))

This community rocks!! @delaguardo

what @delaguardo wrote. Using or is idiomatic.

or is a macro so it is safe to even have some sideeffects in some-alternative function

Thanks a lot !! (and @simongray @delaguardo )

both and and or just return the last value (when true) since everything apart from nil and false is considered true in Clojure, so you will see a lot of succinct code that combines logic tests and nil punning in Clojure code.

Hi there. What is the de facto way in Clojure to check if a string is an email address? Is regex matching my best option here?

There are a lot of resources that will tell you the best you can do is to determine if a string probably is an email address, and not necessarily a valid one.

You can google for some really hairy regexes that are intended to be a comprehensive match for any valid email address, but YMMV.

The site I'm working on now just has a simple regex that checks for "_@_._", and if it doesn't match, it just puts up a caption that says "Please be sure you are using a valid email address."

yeah I forgot how hairy email validation can become with regex

The only reliable way to check for valid email addresses is to send it an email with a link that has an embedded one-time token, and then see if they click the link.

Alternately, there are online services that do mass-mailing that will offer you email validation services, which might be marginally better than a regex, if you don't mind paying.

I'm thinking like MailGun or MailChimp or something, but I don't remember which of them (if any) offers that service. I have seen it though.

This is for a personal project so I’ll just do some simply regex matching. Thanks a lot 🙂

:thumbsup:

@rextruong first 8-9 minutes ofhttps://www.youtube.com/watch?v=9Q--oX5muxw covers email parsing with regexes

tl;dw "good luck" 🙂

The phrase "exponentially diminishing returns" does come to mind 🙂

There’s some java libraries like https://javaee.github.io/javamail/, but the simplest regex + sending an email is really best

I feel very stupid right now because this must be so basic and I can't figure it out... I want to create a function that wraps hiccup content

(defn wrap [content] ; content is a list of hiccup elements
  [:div {:id "Test"}
   ; insert content here, but not in a list, just all the individual elements
   [:div {:id "footer"} ...]
  ])

You could use into effectively here.

you have a vector and a collection and want to return a vector of the concatenation. (into [:div {:id "footer"}] your-collection) is the most straightforward approach

I phrased it like this to point that the smallest reproduction of your issue doesn't have hiccup or divs or a function called wrap involved. often all these details mask the simple problem: (into [:a] [:b :c :d]) -> [:a :b :c :d]

hm ok I was hoping to be able to do something like in js where you can do

let arr1 = [1, 2, 3];
let arr2 = [...arr1, 4, 5, 6];

there's no equivalent of the spread operator in clojure

okay thanks!

kind of interesting, I'd think that'd be a pretty cool thing to have

makes everything more succinct

you can post on http://ask.clojure.org . It's possible it's been brought up before. Possibly declined, possibly still open to it. Or perhaps no one has taken the time to ask about it

so my function would look like this:

(defn wrap [content] ; content is a list of hiccup elements
  (let [wrapper [:div {:id "test"}]
        footer  [
		          ; some more elements here
				]]
  (into (into wrapper content) footer)

in JS I would've done

let wrap = (content) => [
   :div, {:id "test"},
   ...content,
   // footer elements
];

(reduce into wrapper [content footer])

or (into wrapper (concat content footer)) should work

(-> wrapper
    (into content)
    (into footer))

Don’t recall anyone asking for it

I mean, there’s concat, and cat transducer if you want vector

honestly idk why this wasn't obvious to any of us 😄

(concat wrapper content footer)

it needs to be a vector for hiccup

so you'd have to do (into [] (concat ...)) which is what i put above (into wrapper (concat content footer))

I see, yeah

thanks everyone

for some reason I like (vec (concat wrapper content footer)) best, just gets my intent across I feel

That works too.

So let's say i've got a series of posts on a social-ish thing...

and I want to have notifications for users... like if someone "reacts" to your post.

i'm thinking: keep a "last-seen-notification" timestamp for each user, and then check it against the stored reactions... but i also want a way for users to mark certain notifications as seen... well i don't know if i want to go that fine-grain... but in general a way to see notifications for reactions. does it make sense to...

mark notifications as "seen" ... or try and simply rely on latest-seen timestamp to do that difference?

kinda a nebulous design-level question... but i'm a little unclear on doing the notifications bit so any words of help would be appreciated 😄

most notification systems are really bad, because when they were initially written the idea was "little ephemeral messages"

but no one actually wants that, what they want is basically "lightweight email"

meaning an inbox, where notifications persist, and you can mark them as read, and read old ones, etc

so I would try to ignore that you are implementing notifications, and instead look at imap, and the extensions to imap for push, for inspiration

thank you

that makes sense, "lightweight email." I am trying to keep a very reduced interface but a historical view on notifications is likely necessary.

Do you reckon "mark as read/seen" and "Mark all as read/seen" would be sufficient with a boolean on each notif?

hard-pressed to think of other use-cases.

if this is evaluated lazily, shouldn't i receive a false instead of an NPE?

(first (remove #(% nil) [int? zero?]))

(int? nil) => false
  (zero? nil) => NPE