php print callable function

Question

I'm trying to solve a problem :

function f($callable_function){
   print_r($callable_function);// doesn't work at all, of course
}

f(function(){echo "hello World"});

I get the Closure Object element with my print_r function. Is there a way to get :

//OUTPUT RESULT
echo "hello World";

EDIT

The purpose of this is to get the function declaration inside a String (for database later). The f function can be used by any developer so the idea is to make this as simple as possible, that means I don't want the developer to declare his function inside of a String.

PHP is not JavaScript, you cannot print out source code like that... — ItalyPaleAle, Aug 26 '14 at 13:22
If you want to actually execute the function and get the output from it, then do so, I don't know what you thought you would get by using `print_r` on it. — Mike Brant, Aug 26 '14 at 13:35
I know php doesn't work like javascript but is there a way to get the function declaration into a string, I don't want to execute the function itself. — d3cima, Aug 26 '14 at 13:36
Why a function made to dump an array should do something so ? — Brewal, Aug 26 '14 at 13:36
I'm just searching a way to get the declaration, the idea is to store the function declaration. — d3cima, Aug 26 '14 at 13:37
You will get better answers if you describe *what* you are trying to *achieve*, instead of describing *how* you fail with a solution you think is correct. Classic XY problem. — N.B., Aug 26 '14 at 13:47

score 4 · Accepted Answer · answered Feb 28 '19 at 09:27

Never closed this question but I have the answer since 2014 :

 $reflFunc = new ReflectionFunction($callable);
 $filename = $reflFunc->getFileName()); 
 $startline = $reflFunc->getStartLine(); 
 $endline = $reflFunc->getEndLine();

And using preg_match, I can extract what I need. (as suggested by the first answer)

Fractaliste · Answer 2 · 2014-08-26T13:46:13.873

0

You can get the PHP file as a string and then find the function (the following exemple is a very quick one, it should be improved):

function f($callable_function) {
    $f = file_get_contents(__FILE__);
    preg_match("#function $callable_function\(.*\)[^\{]*{(.*)}#Us", $f, $matches);
    var_dump($matches);
}

function a() {
    echo "hello World";
}

f('a');

But there is some limitations:

It can be complicated if you have many PHP files for instance
My exemple not supports character { into the body of the function, but this can be improved by somebody good at regex
It doesn't work with anonymous callbacks (and maybe with object's method)

edited Aug 26 '14 at 13:46

answered Aug 26 '14 at 13:24

Fractaliste

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I like this solution, this may be a replacement to my solution, but I would be happy to use anonymous functions. But thank you for you help :-) – d3cima Aug 26 '14 at 14:33
This answer helped a lot : Insted of preg_match function name, I used : $reflFunc = new ReflectionFunction($callable); $file = file_get_contents($reflFunc->getFileName()); $reflFunc->getStartLine(); $reflFunc->getEndLine(); – d3cima Aug 26 '14 at 22:49
if the function is declared dynamically (callable sometime is), then this could be long search for right file across the project – Jimmmy Feb 20 '19 at 17:03

php print callable function

2 Answers2