<?php
/**
* @package s9e\TextFormatter
* @copyright Copyright (c) 2010-2021 The s9e authors
* @license http://www.opensource.org/licenses/mit-license.php The MIT License
*/
namespace s9e\TextFormatter\Configurator\Validators;
use InvalidArgumentException;
/**
* Template parameter name rules:
* - must start with a letter or an underscore
* - can only contain letters, numbers and underscores
*
* This is much more restrictive than the XSL specs
*/
abstract class TemplateParameterName
{
/**
* Return whether a string is a valid parameter name
*
* @param string $name Parameter name
* @return bool
*/
public static function isValid($name)
{
return (bool) preg_match('#^[a-z_][-a-z_0-9]*$#Di', $name);
}
/**
* Normalize a template parameter name
*
* @param string $name Original name
* @return string Normalized name
*/
public static function normalize($name)
{
$name = (string) $name;
if (!static::isValid($name))
{
throw new InvalidArgumentException("Invalid parameter name '" . $name . "'");
}
return $name;
}
}