ryangraham

#!/usr/bin/env bash
set -o errexit
set -o pipefail
set -o nounset
set -o xtrace

GIT_ROOT=$(git rev-parse --show-toplevel)
pushd "$GIT_ROOT" || exit

CURRENT_BRANCH=$(git rev-parse --abbrev-ref HEAD)

ryangraham

#Get a value from nested maps

The get_in function can be used to retrieve a nested value in nested maps using a list of keys.

nested_map = %{ name: %{ first_name: "blackode"} }     #Example of Nested Map
first_name = get_in(nested_map, [:name, :first_name])  # Retrieving the Key

# Returns nil for missing value 
nil = get_in(nested, [:name, :last_name])              # returns nil when key is not present

ryangraham

$ iex
Erlang/OTP 22 [erts-10.4.3] [source] [64-bit] [smp:12:12] [ds:12:12:10] [async-threads:1] [hipe]

Interactive Elixir (1.11.0-dev) - press Ctrl+C to exit (type h() ENTER for help)
iex(1)> as_binary = &IO.inspect(&1, base: :binary)
#Function<7.91303403/1 in :erl_eval.expr/5>
iex(2)> ?a..?z |> Enum.each(as_binary)
0b1100001
0b1100010
0b1100011

ryangraham

$ make
g++ -std=c++11 main.cpp
./a.out
123456789abcdef
123456789ABCDEF

ryangraham

#include <string>
#include <iostream>

char to_upper(char c)
{
    // between 97 and 122?
    if (c >= 'a' && c <= 'z')
        return c ^ 32; // unset 6th bit

    return c;

ryangraham

ryangraham

ryangraham

  // track2 4-bit BCD encode
  std::string track2 = ";4088490010739415=24082260007000?3";
  std::string encoded = "";
  uint8_t acc = 0;
  bool full = false;
  for (uint8_t c : track2)
  {
      if (!full)
      {
          acc = c - 0x30;

ryangraham

    // track2 decode
    std::string decoded = "";
    uint8_t left = 0;
    uint8_t right = 0;
    for (uint8_t c : encoded)
    {
        left = c >> 4;
        right = c & 0b00001111;
        decoded.append(1, left + 0x30);
        decoded.append(1, right + 0x30);

ryangraham

#include <iostream>
#include <string>
#include <termios.h>
#include <unistd.h>

int password_prompt(std::string &password)
{
    struct termios tty;

    // Get current terminal settings