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 3.0.184

Twitter updates

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    17 September 2021
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    27 August 2021

Latest news

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    In the 384th issue of ProcessWire Weekly we'll cover the latest core updates, introduce a new module called Session Allow, and highlight a new site of the week. Read on!
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    This week we have a new master/main version released after a full year in the making. As you might imagine, this new version has a ton of great new stuff and we’ll try to cover much of it here.
    Blog / 27 August 2021
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