Bench basename() for namespaced class names

bench.basename.php

<?php
# Simple PHP 5.4+ bench script for CLI.

const ITERATIONS = 10000;

error_reporting(E_ALL | E_STRICT);
setlocale(LC_ALL, 'C');
register_shutdown_function(function () {
  echo PHP_EOL;
  $memory_peak_end = memory_get_peak_usage();
  echo 'Peak memory after test: ', format_kb($memory_peak_end), PHP_EOL;
  echo 'Memory difference: ', format_kb($memory_peak_end, MEMORY_PEAK_START), PHP_EOL;
});
function format_kb($size, $diff_base_size = NULL) {
  $out = '';
  if (isset($diff_base_size)) {
    $out = ($size = $size - $diff_base_size) > 0 ? '+' : '';
  }
  $out .= number_format($size / 1024) . ' KB';
  return $out;
}
function no_op($text) {
  return $text;
}

/**
 * Initialization.
 */
define('MEMORY_PEAK_START', memory_get_peak_usage());
echo 'Peak memory before test: ', format_kb(MEMORY_PEAK_START), PHP_EOL;
echo 'Iterations: ', ITERATIONS, PHP_EOL, PHP_EOL;

/**
 * Test cases.
 */
$tests['nothing'] = function () {
};
$tests['no_op'] = function () {
  $text = no_op('some string');
};

$classes = ['Sun\Tests\StaticReflection\Fixtures\Example', '\Example', 'Example'];

rerun:
$class = array_shift($classes);
echo '--- ', $class, "\n";

$tests['basename'] = function () use ($class) {
  return basename($class);
};
$tests['explode'] = function () use ($class) {
  $parts = explode('\\', $class);
  return end($parts);
};
$tests['preg_match'] = function () use ($class) {
  preg_match('/[^\\\\]+$/', $class, $matches);
  return $matches[0];
};
$tests['maxnimble/sun'] = function () use ($class) {
  return array_slice(explode('\\', $class), -1)[0];
};
$tests['maxnimble'] = function () use ($class) {
  return join('', array_slice(explode('\\', $class), -1));
};
$tests['strrpos'] = function () use ($class) {
  return ltrim(substr($class, strrpos($class, '\\')), '\\');
};
$tests['strtok'] = function () use ($class) {
  $token = strtok($class, '\\');
  while ($token !== FALSE) {
    $part = $token;
    $token = strtok('\\');
  }
  return $part;
};

/**
 * Test runner.
 */
$results = array();
foreach ($tests as $name => $test) {
  $start = microtime(true);
  for ($i = 0; $i < ITERATIONS; ++$i) {
    $results[$name] = $test();
  }
  $stop = microtime(true);
  printf("%-20.20s %2.3f seconds -- %s\n", $name . ':', $stop - $start, var_export($results[$name], TRUE));
}

if ($classes) {
  echo "\n";
  goto rerun;
}

gistfile1.sh-session

$ php bench.basename.php
Peak memory before test: 151 KB
Iterations: 100000

--- Sun\Tests\StaticReflection\Fixtures\Example
nothing:             1.122 seconds -- NULL
no_op:               1.554 seconds -- NULL
basename (Windows):  1.859 seconds -- 'Example'
explode:             2.140 seconds -- 'Example'
preg_match:          2.274 seconds -- 'Example'
maxnimble/sun:       2.161 seconds -- 'Example'
maxnimble:           2.598 seconds -- 'Example'
strrpos:             2.434 seconds -- 'Example'
strtok:              3.851 seconds -- 'Example'

--- \Example
nothing:             1.125 seconds -- NULL
no_op:               1.548 seconds -- NULL
basename (Windows):  1.630 seconds -- 'Example'
explode:             2.066 seconds -- 'Example'
preg_match:          1.802 seconds -- 'Example'
maxnimble/sun:       2.111 seconds -- 'Example'
maxnimble:           2.581 seconds -- 'Example'
strrpos:             2.473 seconds -- 'Example'
strtok:              2.104 seconds -- 'Example'

--- Example
nothing:             1.106 seconds -- NULL
no_op:               1.512 seconds -- NULL
basename (Windows):  1.634 seconds -- 'Example'
explode:             2.061 seconds -- 'Example'
preg_match:          1.840 seconds -- 'Example'
maxnimble/sun:       2.103 seconds -- 'Example'
maxnimble:           2.513 seconds -- 'Example'
strrpos:             2.439 seconds -- 'Example'
strtok:              2.057 seconds -- 'Example'

Peak memory after test: 151 KB
Memory difference: +1 KB