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defined
defined
Check if a constant with a name exists
Name:
defined
Category:
Miscellaneous
Programming Language:
php
One-line Description:
Check if the constant exists.
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Popular Articles
How to Use PHP’s defined() Function to Prevent Constant Redefinition Conflicts
What is the defined() Function in PHP? How to Use It to Check if a Constant Is Already Defined?
Combining defined() and require_once: How to Prevent PHP Files from Being Loaded Multiple Times
What Are the Practical Uses of the defined() Function in PHP Conditional Statements?
How to Use PHP's defined() Function to Dynamically Check and Create Constants: Practical Tips
The combined use of defined() and constant() function