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phpconstantsdefined

PHP defined not working?

I have a config file that I include early in my program and set this

define('BASE_SLUG','/shop');

I include another file later with these lines

echo BASE_SLUG;
if (defined(BASE_SLUG)) {
  echo ' - yes';
} else {
  echo ' - no';
}

And my output is

/shop - no

how is this possible? BASE_SLUG has the value of /shop and I can echo it, but one line later it says it is not defined

Solution

  • Here is the function prototype for defined

    bool defined ( string $name )

    You can see that it expects a string value for a constant name. Yours isn't a valid string.

    if (defined(BASE_SLUG)) {

    Should have the name of constant inside quotes, like :

    if (defined('BASE_SLUG')) {

    Read this note from PHP Manual

    <?php
/* Note the use of quotes, this is important.  This example is checking
 * if the string 'TEST' is the name of a constant named TEST */
if (defined('TEST')) {
    echo TEST;
}
?>

    Source