spqr/vendor/cakephp/database/Expression/UnaryExpression.php

119 lines
2.8 KiB
PHP
Raw Normal View History

2024-11-05 12:10:06 +08:00
<?php
declare(strict_types=1);
/**
* CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
* Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
*
* Licensed under The MIT License
* For full copyright and license information, please see the LICENSE.txt
* Redistributions of files must retain the above copyright notice.
*
* @copyright Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
* @link https://cakephp.org CakePHP(tm) Project
* @since 3.0.0
* @license https://opensource.org/licenses/mit-license.php MIT License
*/
namespace Cake\Database\Expression;
use Cake\Database\ExpressionInterface;
use Cake\Database\ValueBinder;
use Closure;
/**
* An expression object that represents an expression with only a single operand.
*/
class UnaryExpression implements ExpressionInterface
{
/**
* Indicates that the operation is in pre-order
*
* @var int
*/
public const PREFIX = 0;
/**
* Indicates that the operation is in post-order
*
* @var int
*/
public const POSTFIX = 1;
/**
* The operator this unary expression represents
*
* @var string
*/
protected $_operator;
/**
* Holds the value which the unary expression operates
*
* @var mixed
*/
protected $_value;
/**
* Where to place the operator
*
* @var int
*/
protected $position;
/**
* Constructor
*
* @param string $operator The operator to used for the expression
* @param mixed $value the value to use as the operand for the expression
* @param int $position either UnaryExpression::PREFIX or UnaryExpression::POSTFIX
*/
public function __construct(string $operator, $value, $position = self::PREFIX)
{
$this->_operator = $operator;
$this->_value = $value;
$this->position = $position;
}
/**
* @inheritDoc
*/
public function sql(ValueBinder $binder): string
{
$operand = $this->_value;
if ($operand instanceof ExpressionInterface) {
$operand = $operand->sql($binder);
}
if ($this->position === self::POSTFIX) {
return '(' . $operand . ') ' . $this->_operator;
}
return $this->_operator . ' (' . $operand . ')';
}
/**
* @inheritDoc
*/
public function traverse(Closure $callback)
{
if ($this->_value instanceof ExpressionInterface) {
$callback($this->_value);
$this->_value->traverse($callback);
}
return $this;
}
/**
* Perform a deep clone of the inner expression.
*
* @return void
*/
public function __clone()
{
if ($this->_value instanceof ExpressionInterface) {
$this->_value = clone $this->_value;
}
}
}