.. _increment-on-non-numeric-string-is-deprecated,-use-str_increment()-instead:

Increment on non-numeric string is deprecated, use str_increment() instead
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Description
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PHP 8.3 introduced str_increment() and str_decrement(), which update strings by changing the last character's ascii code. It mirrors a famous PHP easter egg, where a string may be incremented with the ``++`` operator. 

In PHP 8.5, this feature is deprecated, and a warning is emitted. There is no deprecation warning for decrementing, as the feature was not implemented on strings.

Example
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.. code-block:: php

   <?php
   
       $string = 'aa';
       ++$string;
   
       echo $string;
   
   ?>

Solutions
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+ Use str_increment(), instead of ``++`` on string variables.

Changed Behavior
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This error may appear following an evolution in behavior, in previous versions. See `incrementNonAlphanumeric <https://php-changed-behaviors.readthedocs.io/en/latest/behavior/incrementNonAlphanumeric.html>`_.

Static Analysis
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This error may be tracked down with the following static analysis rules: `Php/PlusPlusOnLetters <https://exakat.readthedocs.io/en/latest/Reference/Rules/Php/PlusPlusOnLetters.html>`_.