wireEmpty() function

Is the given value empty according to ProcessWire standards?

This works the same as PHP’s empty() function except for the following:

  • It returns true for Countable objects that have 0 items.
  • It considers whitespace-only strings to be empty.
  • It considers WireNull objects (like NullPage or any others) to be empty (3.0.149+).
  • It uses the string value of objects that can be typecast strings (3.0.150+).
  • You cannot pass it an undefined variable without triggering a PHP warning.

Available since version 3.0.143.

Example

// behavior with Countable objects
$a = new WireArray();
empty($a); // PHP’s function returns false
wireEmpty($a); // PW’s function returns true
$a->add('item');
wireEmpty($a); // returns false, since there is now an item

// behavior with whitespace-only string
$s = '  ';
empty($s); // PHP’s function returns false
wireEmpty($s); // PW’s function returns true

// behavior with undefined variable $v
isset($v); // returns false
empty($v); // returns true
wireEmpty($v); // returns true but with PHP’s warning triggered

Usage

$bool = wireEmpty(mixed $value);

Arguments

NameType(s)Description
valuemixed

Value to test if empty

Return value

bool


Functions methods and properties

API reference based on ProcessWire core version 3.0.160

Twitter updates

  • ProcessWire 3.0.161 adds support for selector operator stacking, enabling you automatically broaden searches in a single pages.find() call— More
    26 June 2020
  • ProcessWire 3.0.160 adds powerful new text-searching operators, bringing a new level of power to page-finding API calls, especially when it comes to search engine type queries. Post also includes a demo search engine where you can test it all out live— More
    19 June 2020
  • Preview of ProcessWire 3.0.160 with auto-enable of two-factor authentication, new version of TfaEmail and TfaTotp, and new selector operators coming next week. More
    12 June 2020

Latest news

  • ProcessWire Weekly #320
    In the 320th issue of ProcessWire Weekly we're going to check out the latest core updates (ProcessWire 3.0.161), a new third party module called Fieldtype Runtime only, an IndieWeb themed article from Francesco Schwarz, and more. Read on!
    Weekly.pw / 27 June 2020
  • Powerful new text-searching abilities in 3.0.160
    In ProcessWire 3.0.160 we’ve got some major upgrades and additions to our text-search abilities. This brings a whole new level of power to $pages->find() and similar API calls, especially when it comes to search engine type queries.
    Blog / 19 June 2020
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I just love the easy and intuitive ProcessWire API. ProcessWire rocks!” —Jens Martsch, Web developer