PHP Function Redefinition and Renaming
In PHP, functions cannot be redefined by simply rewriting them. Attempting to do so, as shown below, will result in an error:
<code class="php">function this($a){
return $a;
}
function this($a, $b){ //New this function
return $a * $b;
}</code>
Error:
Fatal error: Cannot redeclare foo()
To redefine or rename a function in PHP, you can use the runkit extension. It provides functions such as runkit_function_rename() and runkit_function_redefine().
For example, to rename the this function to another, you can use runkit_function_rename():
<code class="php">runkit_function_rename('this', 'another');</code>
To redefine the this function such that it takes two arguments and multiplies them, you can use runkit_function_redefine():
<code class="php">runkit_function_redefine('this', '$a, $b', '$a * $b');</code>The above is the detailed content of How to Redefine and Rename PHP Functions?. For more information, please follow other related articles on the PHP Chinese website!
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