src/NXP/Classes/Token/TokenUnequal.php


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53

<?php

namespace NXP\Classes\Token;

use NXP\Exception\IncorrectExpressionException;

class TokenUnequal extends AbstractOperator
{
    /**
     * @return string
     */
    public static function getRegex()
    {
        return '\!\=';
    }

    /**
     * @return int
     */
    public function getPriority()
    {
        return 140;
    }

    /**
     * @return string
     */
    public function getAssociation()
    {
        return self::LEFT_ASSOC;
    }

    /**
     * @param InterfaceToken[] $stack
     *
     * @return $this
     *
     * @throws \NXP\Exception\IncorrectExpressionException
     */
    public function execute(&$stack)
    {
        $op2 = array_pop($stack);
        $op1 = array_pop($stack);

        if ($op1 === null || $op2 === null) {
            throw new IncorrectExpressionException("!= requires two operators");
        }

        $result = $op1->getValue() != $op2->getValue();

        return new TokenNumber($result);
    }
}