ChrisBlom

(defn non-caching-riemann-client
  [{:keys [host port] :as riemann-config}]
  (assert host)
  (assert port)
  (let [c  (riemann.client/tcp-client :host host :port port)]
    ;; disable dns caching
    ;; If we let riemann cache dns lookups, it can't reconnect to the riemann server after that restarts
    (-> c
        .transport
        .transport

ChrisBlom

;; fontlock logic vars (for datomic and cascalog)
    (font-lock-add-keywords
     'clojure-mode
     `((,(concat "\\<"
		 "\\?[a-z0-9-]+"
		 "\\>")
	0
	font-lock-keyword-face)))

ChrisBlom

(defmacro eval-with-bindings [bindings form]
  (assert (even? (count bindings)) "an even number of forms in binding vector")
  (let [binding-pairs (partition 2 bindings)
        args (mapv first binding-pairs)
        vals (map second binding-pairs)]
    `((eval (fn ~args ~form))
      ~@vals)))

(let [foo inc]
  (eval '(foo 1)))

ChrisBlom

;; Toggle a counter that tracks how manny times a function is called 

(defn instrument-fn [f]
  (let [counter (atom 0)]
    (-> (fn [& args] ;; NOTE could unroll for 1-n args for speed
          (swap! counter inc)
          (apply f args))
        (with-meta
          {:uninstrumented f
           :counter counter}))))

ChrisBlom

{"AWSTemplateFormatVersion":"2010-09-09",
 "Description":"Creates a classic-link enabled VPC, the custom resource hangs",
 "Parameters":{},
 "Resources":
 {"VPC":
  {"Type":"AWS::EC2::VPC",
   "Properties":
   {"EnableDnsSupport":true,
    "EnableDnsHostnames":true,
    "CidrBlock":"10.0.0.0/16",

ChrisBlom

sudo wget http://repos.fedorapeople.org/repos/dchen/apache-maven/epel-apache-maven.repo -O /etc/yum.repos.d/epel-apache-maven.repo
sudo sed -i s/\$releasever/6/g /etc/yum.repos.d/epel-apache-maven.repo
sudo yum install -y apache-maven
mvn --version

ChrisBlom

(defn invert
  "inverts a graph represented as a map from source to target nodes"
  [graph]
  (reduce-kv (fn [acc src trgs]
               (if (seq trgs)
                 (reduce (fn [acc- trg]
                           (update acc- trg (fnil conj #{}) src))
                         acc
                         trgs)
                 ;; to preserve nodes without edges

ChrisBlom

(defun add-clj-format-before-save ()
  (interactive)
  (add-hook 'before-save-hook
            'cider-format-buffer
            t
	    t))

(add-hook 'clojure-mode-hook 'add-clj-format-before-save)

ChrisBlom

  (let [l [0 0 1 1 1 14 5 13 6 3 ]
      m   [0.01 0.02 0.05 0.1 0.2 0.5 1 2 5 10 20 50 100]
      subtotals (map * m l)
      total (reduce + subtotals)]
  (doseq [[munt totaal]  (sort-by key > (zipmap m subtotals))]
    (printf "%s\t%.2f%n" munt (float totaal)))
  total)

ChrisBlom

import io.micrometer.core.instrument.MeterRegistry
import io.micrometer.core.instrument.Tag
import java.time.Instant
import java.util.concurrent.TimeUnit
import java.util.concurrent.atomic.AtomicLong
import java.util.function.ToDoubleFunction

fun MeterRegistry.timeGaugeMillis(name: String, tags: Iterable<Tag>, initialValue: Long = 0): (Instant) -> Unit {
    val a = AtomicLong(initialValue)
    a.apply {