gistfile1.txt

	public function getRelativePathFrom(self $reference)
	{
		$referencePath = static::cleanPath($reference);

		switch (true)
		{
			case $this->path == $referencePath:
				return '.';

			case $referencePath == '':
				return '.' . $this->path;

			case $this->isSubPathOf($referencePath):
				return './' . substr($this->path, strlen($referencePath) + 1);

			default:
				$relativePath = '';

				while ($this->isNotSubPathOf($referencePath))
				{
					$relativePath .= '../';

					$referencePath = dirname($referencePath);
				}

				return static::cleanPath($relativePath) . '/' . ltrim(substr($this->path, strlen($referencePath)), '/');
		}
	}

	protected function isSubPathOf($path)
	{
		return ($path == '/' || strpos($this->path, $path . '/') === 0);
	}

	protected function isNotSubPathOf($path)
	{
		return ($this->isSubPathOf($path) === false);
	}

	protected static function cleanPath($path)
	{
		return rtrim($path, '/');
	}