Online PHP editor | refs for anJku

<?php namespace GeneratorExample; class Pipeline { protected $generators; function __construct() { $this->generators = new \SplStack; } function add(callable $generator) { $this->generators->push($generator); return $this; } function resolve() { $inputs = func_get_args(); foreach ($this->generators as $g) { $generator = call_user_func_array($g, $inputs); $inputs = [$generator]; } return $generator; } } function uppercase(\Traversable $in) { foreach ($in as $word) { yield strtoupper($word); } } function reverse(\Traversable $in) { foreach ($in as $word) { yield strrev($word); } } function each_println(\Traversable $in) { foreach ($in as $line) { echo "$line\n"; } } $words = new \ArrayIterator(["foo", "bar", "baz"]); $p = new Pipeline; $p->add("GeneratorExample\\uppercase")->add("GeneratorExample\\reverse")->add("GeneratorExample\\each_println"); $p->resolve($words);