Milo\Github\Api::expandUriTemplate PHP Method

    protected function expandUriTemplate($url, array $parameters, array $defaultParameters)
    {
        $parameters += $defaultParameters;
        static $operatorFlags = ['' => ['prefix' => '', 'separator' => ',', 'named' => FALSE, 'ifEmpty' => '', 'reserved' => FALSE], '+' => ['prefix' => '', 'separator' => ',', 'named' => FALSE, 'ifEmpty' => '', 'reserved' => TRUE], '#' => ['prefix' => '#', 'separator' => ',', 'named' => FALSE, 'ifEmpty' => '', 'reserved' => TRUE], '.' => ['prefix' => '.', 'separator' => '.', 'named' => FALSE, 'ifEmpty' => '', 'reserved' => FALSE], '/' => ['prefix' => '/', 'separator' => '/', 'named' => FALSE, 'ifEmpty' => '', 'reserved' => FALSE], ';' => ['prefix' => ';', 'separator' => ';', 'named' => TRUE, 'ifEmpty' => '', 'reserved' => FALSE], '?' => ['prefix' => '?', 'separator' => '&', 'named' => TRUE, 'ifEmpty' => '=', 'reserved' => FALSE], '&' => ['prefix' => '&', 'separator' => '&', 'named' => TRUE, 'ifEmpty' => '=', 'reserved' => FALSE]];
        return preg_replace_callback('~{([+#./;?&])?([^}]+?)}~', function ($m) use($url, &$parameters, $operatorFlags) {
            $flags = $operatorFlags[$m[1]];
            $translated = [];
            foreach (explode(',', $m[2]) as $name) {
                $explode = FALSE;
                $maxLength = NULL;
                if (preg_match('~^(.+)(?:(\\*)|:(\\d+))$~', $name, $tmp)) {
                    // TODO: Speed up?
                    $name = $tmp[1];
                    if (isset($tmp[3])) {
                        $maxLength = (int) $tmp[3];
                    } else {
                        $explode = TRUE;
                    }
                }
                if (!isset($parameters[$name])) {
                    // TODO: Throw exception?
                    continue;
                }
                $value = $parameters[$name];
                if (is_scalar($value)) {
                    $translated[] = $this->prefix($flags, $name, $this->escape($flags, $value, $maxLength));
                } else {
                    $value = (array) $value;
                    $isAssoc = key($value) !== 0;
                    // The '*' (explode) modifier
                    if ($explode) {
                        $parts = [];
                        if ($isAssoc) {
                            $this->walk($value, function ($v, $k) use(&$parts, $flags, $maxLength) {
                                $parts[] = $this->prefix(['named' => TRUE] + $flags, $k, $this->escape($flags, $v, $maxLength));
                            });
                        } elseif ($flags['named']) {
                            $this->walk($value, function ($v) use(&$parts, $flags, $name, $maxLength) {
                                $parts[] = $this->prefix($flags, $name, $this->escape($flags, $v, $maxLength));
                            });
                        } else {
                            $this->walk($value, function ($v) use(&$parts, $flags, $maxLength) {
                                $parts[] = $this->escape($flags, $v, $maxLength);
                            });
                        }
                        if (isset($parts[0])) {
                            if ($flags['named']) {
                                $translated[] = implode($flags['separator'], $parts);
                            } else {
                                $translated[] = $this->prefix($flags, $name, implode($flags['separator'], $parts));
                            }
                        }
                    } else {
                        $parts = [];
                        $this->walk($value, function ($v, $k) use(&$parts, $isAssoc, $flags, $maxLength) {
                            if ($isAssoc) {
                                $parts[] = $this->escape($flags, $k);
                            }
                            $parts[] = $this->escape($flags, $v, $maxLength);
                        });
                        if (isset($parts[0])) {
                            $translated[] = $this->prefix($flags, $name, implode(',', $parts));
                        }
                    }
                }
            }
            if (isset($translated[0])) {
                return $flags['prefix'] . implode($flags['separator'], $translated);
            }
            return '';
        }, $url);
    }