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(defn find-case-insensitive
  [db attr val]
  (let [a (dq/qe-or-nil
           '[:find ?account
             :in $ ?pattern ?attr
             :where
             [?account ?attr ?name]
             [(re-find ?pattern ?name)]]
           db
           (re-pattern (str "(?i)^" val "$")) attr)]

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(loop [o (init-obj)]
  (when-let [o (try (something-risky)
                    (catch Exception e (record-exception! e)))]
    (recur o)))

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(ns datomic-helpers
  (:require [clojure.java.io :as io]
            [clojure.walk    :as walk]
            [datomic.api     :as d :refer (db)]))

;;; Expose Datomic vars here, for convenience

(def tempid  d/tempid)
(def connect d/connect)
(def create-database d/create-database)

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(defn balance-history [id]
  (d/q '[:find ?tx ?tx-time ?v
       :in $ ?e ?a
       :where [?e ?a ?v ?tx _]
       [?tx :db/txInstant ?tx-time]]
     (d/history (db/db)) id :account/balance))

@(d/transact conn [[:credit 17592186145525 100]])

(balance-history 17592186145525)

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user=> (doc defn)
-------------------------
clojure.core/defn
([name doc-string? attr-map? [params*] prepost-map? body] [name doc-string? attr-map? ([params*] prepost-map? body) + attr-map?])
Macro
  Same as (def name (fn [params* ] exprs*)) or (def
    name (fn ([params* ] exprs*)+)) with any doc-string or attrs added
    to the var metadata. prepost-map defines a map with optional keys
    :pre and :post that contain collections of pre or post conditions.
nil

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// com.google.common.util.concurrent.MoreExecutors

sendResult.broadcastComplete.addListener(new Runnable() {
  @Override
  public void run() {
    System.out.println("Complete!");
  }
}, MoreExecutors.sameThreadExecutor());

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require 'digest'

class String
  def to_seed
    (Digest::SHA256.hexdigest(self).to_i(16))
  end
end

puts "abc".to_seed => 84342368487090800366523834928142263660104883695016514377462985829716817089965
puts "123123123".to_seed => 66573445395556389320569794094825521729047035552620196053537129277119858926575

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(defn fetch-user [username]
  (go
    (let [ch (chan)]
      (letrpc [user (get-user-info username)] ;; shoreleave remote's letrpc macro
        (>! ch user)
        (close! ch))
      ch)))

(defn display-user-info [username]
  (go (let [u (<! (fetch-user username))]

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; how would you write this function summarize?

(summarize [{:from "A" :to "B" :amount 3} {:from "B" :to "A" :amount 1}]) => {:from "A" :to "B" :amount 2}

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; update-vec merges a vector based on the :id's of its contents

(update-vec [{:id 1 :data "1"} {:id 2 :data "2"}] {:id 3 :data "3"})
;=> [[{:id 1 :data "1"} {:id 2 :data "2"} {:id 3 :data "3"}]]

(update-vec [{:id 1 :data "1"} {:id 2 :data "2"}] {:id 2 :data "tonystark"})
;=> [[{:id 1 :data "1"} {:id 2 :data "tonystark"}]]