In PHP, how do I check if a function exists? #coding #programming #phplaravel #function #php

The function_exists() is an inbuilt function in PHP. The function_exists() function is useful in case if we want to check whether a function() exists or not in the PHP script. It is used to check for both built-in functions as well as user-defined functions.

boolean function_exists($function_name)

function_exists — Return true if the given function has been defined
Returns true if function exists and is a function, false otherwise.

Parameter: This function accepts a single parameter $function_name. This is the name of function that we want to search in the list of defined function. This is a string type parameter.

Return Values: This function returns a Boolean value. In case a function with the name $function_name exists it returns TRUE, otherwise it returns FALSE. This function will also return FALSE for constructs like “include_once”, “echo” etc.
Note:
This function will return false for constructs, such as include_once and echo.