John Davidson

Message:

I am new to PHP and Magento2. I was reading some sample code in a PHTML file and came across this style of declaring a variable

<?php

    /** @var \Magento\Theme\Block\Html\Title $title */

?>

And I could use the $title variable as if I had declared and made it an instance of the Title class.

Right below that, there was another piece like so:

<?php

    $text = $title->getPageTitle();

?>

What is the difference between the two styles of declaration?

Importantly, why doesn't Magento2 complain about the undeclared variable $title in this case?

EDIT

It was not

<?php

    /** @var \Magento\Theme\Block\Html\Title $title */

?>

Instead it is written as

<?php

    /** @var \Magento\Theme\Block\Html\Title $block */

?>

The question is still the same, as to how can $block be used without actually declaring it

---

My Answer:
The `@var` annotation in PHP is used to specify the type of a variable in a docblock comment. It is used to provide information about the type of data that a variable should hold, which can be helpful for developers reading the code.

For example, `@var int $myVar` specifies that the variable `$myVar` should hold an integer value.

On the other hand, `[type]` is a type declaration introduced in PHP 7. It is used to specify the type of a parameter or return value in a function declaration. This helps to enforce type checking at compile time and can improve code readability and maintainability.

For example, `function myFunction(int $param): string` specifies that the function `myFunction` expects an integer parameter and will return a string value.

In summary, `@var` is used in docblock comments to specify the type of a variable, while `[type]` is used in function declarations to specify the type of parameters and return values.