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1 point by markkat 5097 days ago | link | parent

Thanks again. Based on the login issue shader pointed out, I decided to change things up a bit, and ++ karma if it is a new day, and the user comments or replies. This is what I did, and it seems to work. I started with process-comment:

  (deftem profile
  ...
  karmadate nil
  ...
  )

  (def process-comment (user parent text ip whence)
  ...
         (day-karma user)
         whence)))

  (def day-karma (u)
    (when (~iso (date) (uvar u karmadate))
      (++ (karma u))
    (update-karmadate u)))

  (def update-karmadate (u)
    (= (uvar u karmadate) (date))
    (save-prof u))
But now looking at akkartik's

  (unless (is (date) (uvar u last-login))
    (++ karma.u)
    (= (uvar u last-login) (date)))
Maybe I'll go for that. BTW, karma.u what's up with the . ?


3 points by shader 5097 days ago | link

Arc has a feature called "ssyntax", short for symbol syntax, that allows us to use certain characters in a symbol as shorthand for a commonly used longer form.

In this case, "karma.u" expands to (karma u), which is a macro that looks up the users karma. Functions applied to single arguments are extremely common in arc, so it is quite useful to have an abbreviation.

Other ssyntax include:

  a!b -> (a 'b)
  ~a -> (no a)
  a~b -> (compose a (no b))
  a:b -> (compose a b) ;(a:b c) is equivalent to (a (b c))

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1 point by markkat 5097 days ago | link

Ah... thanks. Great way to throw noobs like me off though. :) I was wondering about the colon too, I couldn't find an explanation anywhere.

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1 point by akkartik 5097 days ago | link

Don't forget to replace is with iso like rocketnia pointed out.

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1 point by markkat 5097 days ago | link

Will do. Thanks for that.

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