Rethinking Loops

Sandbox - composer create-project johnkary/rethinking-loops

FizzBuzz

• Coding exercise
• Print ‘Fizz’ for multiples of 3
• Print ‘Buzz’ for multiples of 5
• Print ‘FizzBuzz’ for multiples of both
• Otherwise print the number

What if We Used Arrays for Everything?

• Collection oriented programming
• Functional programming

Functional Programming Concepts

• Map - 1:1 transform on a collection
  • array_map(callable $callback, array $array1 [, array $... ])
• Filter - Only keep items whre a condition returns true
  • array_filter(array $array [, callable $callback [, int $flag = 0 ]])
• Reduce - Combine items into something new
  • array_reduce(array $array, callable $callback [, mixed $initial = NULL ])

Closure

function ($param) use ($var) = {
}

Control Structure Anxiety

• Nested control structures :(
• Reduced readibility
• Example:

foreach {
  if () {
    foreach () {
      if () {

      }
    }
  }
  else {
    foreach () {
      if () {

      }
    }
  }
}

Notes

Haystack\HArray - Library for pipelining map, filter and reduce functions (https://github.com/ericpoe/haystack)

new Haystack\HArray($array)
  ->map(...)
  ->filter(...)
  ->reduce(...)
  ->toArray()