What’s New in PHP 7.3 - TechTIQ Solutions

PHP developer - PHP 7 is a major release of PHP programming language and is touted to be a revolution in the way web applications can be developed and delivered for mobile to business and the cloud.

is_countable 

PHP 7.2 added a warning when counting uncountable objects. The is_countable function can help prevent this warning.

$count = is_countable($variable) ? count($variable) : null;

array_key_first and array_key_last 

These two functions basically do what the name says.

$array = [

    'a' => '…',

    'b' => '…',

    'c' => '…',

];

array_key_first($array); // 'a'

array_key_last($array); // 'c'

The original RFC also proposed array_value_first and array_value_last, but these were voted against by the majority of people.

Another idea for array_first and array_last was proposed which would return a tuple [$key => $value], but opinions were mixed. For now, we only have two functions to get the first and last key of an array.

Flexible Heredoc syntax 

Heredoc can be a useful tool for larger strings, though they had an indentation quick in the past.

// Instead of this:

$query = <<<SQL

SELECT * 

FROM `table`

WHERE `column` = true;

SQL;

// You can do this:

$query = <<<SQL

    SELECT * 

    FROM `table`

    WHERE `column` = true;

    SQL;

This is especially useful when you're using Heredoc in an already nested context.

The whitespaces in front of the closing marker will be ignored on all lines.

An important note: because of this change, some existing Heredocs might break, when they are using the same closing marker in their body.

$str = <<<FOO

abcdefg

    FOO

FOO;

// Parse error: Invalid body indentation level in PHP 7.3

Tailing commas in function calls

What was already possible with arrays, can now also be done with function calls. Note that it's not possible in function definitions!

$compacted = compact(

    'posts',

    'units',

);

Better type error reporting

TypeErrors for integers and booleans used to print out that full name, it has been changed to int and bool, to match the type hints in the code.

Argument 1 passed to foo() must be of the type int/bool

In comparison to PHP 7.2:

Argument 1 passed to foo() must be of the type 

integer/boolean

JSON errors can be thrown 

Previously, JSON parse errors were a hassle to debug. The JSON functions now accept an extra option to make them throw an exception on parsing errors. This change obviously adds a new exception: JsonException.

json_encode($data, JSON_THROW_ON_ERROR);

json_decode("invalid json", null, 512, JSON_THROW_ON_ERROR);

// Throws JsonException

While this feature is only available with the newly added option, there's a chance it'll be the default behavior in a future version.

list reference assignment 

The list() and its shorthand [] syntax now support references.

$array = [1, 2];

list($a, &$b) = $array;

$b = 3;

// $array = [1, 3];

Undefined variables in the compact 

Undefined variables passed to compact will be reported with a notice, they were previously ignored.

$a = 'foo';

compact('a', 'b'); 

// Notice: compact(): Undefined variable: b

Case-insensitive constants 

There were a few edge cases were case-insensitive constants were allowed. These have been deprecated.

Same site cookie RFC

This change not only adds a new parameter, it also changes to the way the setcookie, setrawcookie, and session_set_cookie_params functions work in a non-breaking manner.

Instead of one more parameter added to already huge functions, they now support an array of options, whilst still being backward compatible. An example:

bool setcookie(

    string $name 

    [, string $value = "" 

    [, int $expire = 0 

    [, string $path = "" 

    [, string $domain = "" 

    [, bool $secure = false 

    [, bool $httponly = false ]]]]]] 

)

bool setcookie ( 

    string $name 

    [, string $value = "" 

    [, int $expire = 0 

    [, array $options ]]] 

)

// Both ways work.

Several deprecations 

Several small things have been deprecated, there's a possible error can show up in your code because of this.

• Undocumented mbstring function aliases
• String search functions with integer needle
• fgetss() function and string.strip_tags filter
• Defining a free-standing assert() function
• FILTER_FLAG_SCHEME_REQUIRED and FILTER_FLAG_HOST_REQUIREDflags
• pdo_odbc.db2_instance_name php.ini directive

Introduction to TechTIQ Solutions 

TechTIQ Solutions has an expert team in Hire PHP developer, expert, TechTIQ Solutions is a Uk based web design & development agency. We deliver a full range of web solutions that focus on our client’s objectives. Our offerings include all of the traditional aspects of web design and web development with PHP web developer London the emphasis always on helping the clients to achieve their goal.