Laymer

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Laymer

f(MostLeaky).
MostLeaky = fun(N) ->
    lists:sublist(
     lists:usort(
         fun({K1,V1},{K2,V2}) -> {V1,K1} =< {V2,K2} end,
         [try
              {_,Pre} = erlang:process_info(Pid, binary),
              erlang:garbage_collect(Pid),
              {_,Post} = erlang:process_info(Pid, binary),
              {Pid, length(Post)-length(Pre)}

Laymer

=== CALL TRACE OF net_kernel:connect\1

% otp/lib/kernel/src/net_kernel.erl
connect(node_name@machine) -> do_connect(node_name@machine, normal, false). ->
  %          Node,              Type,   WaitForBarred
  do_connect(node_name@machine, normal, false           ) -> %% Type = normal | hidden
    case catch ets:lookup(sys_dist, Node) of
        % [{connection, ...}] if node is in sys_dist
        % []                  if not
	{'EXIT', _} ->

Laymer

% because 256 needs 9 bits to represent it
% although it is 2^8
62> <<256>>.
<<0>>
% because the segments of an Erlang binary
% has to be divisible by 8. Hence
% 1000 0000, 0
57> <<256:9>>.
<<128,0:1>>

Laymer

-module(client_eqc).
-compile(export_all).

-include_lib("eqc/include/eqc.hrl").
-include_lib("eqc/include/eqc_component.hrl").

api_spec() ->
    #api_spec {
      language = erlang,
      modules = [

Laymer

Erlang QuickCheck

What is QuickCheck?

QuickCheck is a language for stating properties of programs.

?FORALL(X, nat(), X*X >= 0)

Laymer

-module(test).

-compile([export_all]).

waitdown(0) -> ok;
waitdown(Count) ->
    receive
        {'DOWN', _, process, _, normal} ->
            waitdown(Count-1)
    end.

Laymer

<script>
var context = new (window.AudioContext || window.webkitAudioContext)();

function start () {
  var source = context.createOscillator();
  var chanMerge = context.createChannelMerger(2);
  var filter = context.createBiquadFilter();

  source.connect(chanMerge, 0, 0);
  source.connect(chanMerge, 0, 1);

Laymer

#!/usr/bin/python

# Credit to frogor for the objc

from Foundation import NSBundle
import json
import objc
import os
import plistlib
import subprocess

Laymer

bool checkCert(JNIEnv *env, jobject contextObject) {
    jclass contextTemp = env->FindClass("android/content/Context");
    jclass contextClass = (jclass) env->NewGlobalRef(contextTemp);
    jmethodID getPackageManager = env->GetMethodID(contextClass,
                                                   "getPackageManager",
                                                   "()Landroid/content/pm/PackageManager;");
    jobject share = (jobject) env->CallObjectMethod(contextObject, getPackageManager);

    jmethodID getPackageName = env->GetMethodID(contextClass, "getPackageName",
                                                "()Ljava/lang/String;");