The Expression Syntax ¶

Accessing Public Properties ¶

Public properties on objects can be accessed by using the . syntax, similar to JavaScript:

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class Apple
{
    public $variety;
}

$apple = new Apple();
$apple->variety = 'Honeycrisp';

var_dump($expressionLanguage->evaluate(
    'fruit.variety',
    [
        'fruit' => $apple,
    ]
));

This will print out Honeycrisp.

Calling Methods ¶

The . syntax can also be used to call methods on an object, similar to JavaScript:

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class Robot
{
    public function sayHi($times)
    {
        $greetings = [];
        for ($i = 0; $i < $times; $i++) {
            $greetings[] = 'Hi';
        }

        return implode(' ', $greetings).'!';
    }
}

$robot = new Robot();

var_dump($expressionLanguage->evaluate(
    'robot.sayHi(3)',
    [
        'robot' => $robot,
    ]
));

This will print out Hi Hi Hi!.

Null-safe Operator ¶

Use the ?. syntax to access properties and methods of objects that can be null (this is equivalent to the $object?->propertyOrMethod PHP null-safe operator):

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// these will throw an exception when `fruit` is `null`
$expressionLanguage->evaluate('fruit.color', ['fruit' => '...'])
$expressionLanguage->evaluate('fruit.getStock()', ['fruit' => '...'])

// these will return `null` if `fruit` is `null`
$expressionLanguage->evaluate('fruit?.color', ['fruit' => '...'])
$expressionLanguage->evaluate('fruit?.getStock()', ['fruit' => '...'])

Arithmetic Operators ¶

• + (addition)
  + (加算)
• - (subtraction)
  - (減算)
• * (multiplication)
  * (乗算)
• / (division)
  / （分割）
• % (modulus)
  ％ （係数）
• ** (pow)
  ** (パウ)

For example:

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var_dump($expressionLanguage->evaluate(
    'life + universe + everything',
    [
        'life' => 10,
        'universe' => 10,
        'everything' => 22,
    ]
));

This will print out 42.

Bitwise Operators ¶

• & (and)
  ＆ （と）
• | (or)
  | | （また）
• ^ (xor)
  ^ (xor)

Comparison Operators ¶

• == (equal)
  == (等しい)
• === (identical)
  === (同一)
• != (not equal)
  != (等しくない)
• !== (not identical)
  !== (同一ではない)
• < (less than)
  < (未満)
• > (greater than)
  > (より大きい)
• <= (less than or equal to)
• >= (greater than or equal to)
  >= (以上)
• matches (regex match)
  一致 (正規表現一致)
• contains
  含む
• starts with
  で始まる
• ends with
  で終わる

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$expressionLanguage->evaluate('not ("foo" matches "/bar/")'); // returns true

Examples:

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$ret1 = $expressionLanguage->evaluate(
    'life == everything',
    [
        'life' => 10,
        'everything' => 22,
    ]
);

$ret2 = $expressionLanguage->evaluate(
    'life > everything',
    [
        'life' => 10,
        'everything' => 22,
    ]
);

Both variables would be set to false.

Logical Operators ¶

• not or !
  または！
• and or &&
• or or ||
  またはまたは ||

For example:

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$ret = $expressionLanguage->evaluate(
    'life < universe or life < everything',
    [
        'life' => 10,
        'universe' => 10,
        'everything' => 22,
    ]
);

This $ret variable will be set to true.

String Operators ¶

• ~ (concatenation)
  ~ (連結)

For example:

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var_dump($expressionLanguage->evaluate(
    'firstName~" "~lastName',
    [
        'firstName' => 'Arthur',
        'lastName' => 'Dent',
    ]
));

This would print out Arthur Dent.

Array Operators ¶

• in (contain)
  に (含む)
• not in (does not contain)
  入っていない (含まない)

For example:

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class User
{
    public $group;
}

$user = new User();
$user->group = 'human_resources';

$inGroup = $expressionLanguage->evaluate(
    'user.group in ["human_resources", "marketing"]',
    [
        'user' => $user,
    ]
);

The $inGroup would evaluate to true.

Numeric Operators ¶

• .. (range)
  .. （範囲）

For example:

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class User
{
    public $age;
}

$user = new User();
$user->age = 34;

$expressionLanguage->evaluate(
    'user.age in 18..45',
    [
        'user' => $user,
    ]
);

This will evaluate to true, because user.age is in the range from 18 to 45.

Ternary Operators ¶

• foo ? 'yes' : 'no'
  ふー？ 'はい・いいえ'
• foo ?: 'no' (equal to foo ? foo : 'no')
  foo ?: 'no' (foo ? foo : 'no' と同じ)
• foo ? 'yes' (equal to foo ? 'yes' : '')
  ふー？ 'はい' (foo に等しい ? 'はい' : '')

Null Coalescing Operator ¶

This is the same as the PHP null-coalescing operator, which combines the ternary operator and isset(). It returns the left hand-side if it exists and it's not null; otherwise it returns the right hand-side. Note that you can chain multiple coalescing operators.

• foo ?? 'no'
  ふー?? '番号'
• foo.baz ?? 'no'
  foo.baz ?? '番号'
• foo[3] ?? 'no'
  フー[3] ?? '番号'
• foo.baz ?? foo['baz'] ?? 'no'
  foo.baz ?? foo['baz'] ?? '番号'