Using return value data typing
PHP 7 allows you to specify a data type for the return value of a function. Unlike scalar type hinting, however, you don't need to add any special declarations.
How to do it...
- This example shows you how to assign a data type to a function return value. To assign a return data type, first define the function as you would normally. After the closing parenthesis, add a space, followed by the data type and a colon:
function returnsString(DateTime $date, $format) : string { return $date->format($format); }
Note
PHP 7.1 introduced a variation on return data typing called nullable types. All you need to do is to change
string
to?string
. This allows the function to return eitherstring
orNULL
. - Anything returned by the function, ...
Get PHP 7 Programming Cookbook now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.