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 3.0.214

Twitter updates

  • This week ProcessWire 3.0.214 is on the dev branch. Relative to 3.0.213 this version has 16 new commits which include the addition of 3 new pull requests, 6 issue fixes, a new WireNumberTools utility class, and various other improvements. More
    17 March 2023
  • ProcessWire 3.0.213 core updates: This week we’ll look at the new WireSitemapXML module, a new WireNumberTools core class, and a new ability for Fieldtype modules to specify useful ready-to-use configurations when creating new fields. More
    24 February 2023
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