print out the expression as well as the value automatically, possible in PHP?

is this possible in PHP? such as

debug_print($s);
debug_print($iInterestRate);
debug_print($date->now());

print out:

$s is Hello World
$iInterestRate is 0.032
$date->now() is 1250403294320

it is possible in C and in Ruby... wonder if something like that is possible in PHP for easy debugging. Thanks very much!

 

Hi winterheat. I think I just responded to your question in another forum so I've copied the post for the benefit of anyone here that may want to know.

--------------------------------------------------------------------------

I'm not familiar with any predefined method that does this in PHP.

A simple way would simply be to print manually such as:

print '$foo is '+$foo;

PHP:

However, I'm assuming that as you're asking the question, you have a lot of variables to debug and therefore want something a bit easier. I found this code on another forum but I haven't had a chance to test it myself.

//============ Function : print_debug( arr result of get_defined_vars,
mixed variable to debug)

function print_debug($defined_vars_array, $debug){

  $unset_unwanted =
array("GLOBALS","_POST","_GET","_COOKIE","_FILES");
  foreach ($unset_unwanted as $remove){
    unset($defined_vars_array[$remove]);
  }

   while ($element = current($defined_vars_array)) {
   if ($element == $debug) {

       if (is_array($debug)){
         echo '$'.key($defined_vars_array).' = <br />'.
print_r($debug, TRUE) . "<br />";
       } else {
         echo '$'.key($defined_vars_array).' = '. $debug . "<br />";
       }
   }
   next($defined_vars_array);
   }

}

//============= End of Function

//=========================================
// somescript.php

// Test Variable
$test_var1 = "This is a test Variable";
$var_test = array(1,2,3);

// debug the variable by calling "print_debug()"

$arr = get_defined_vars();
print_debug($arr,$var_test); 

PHP:

Source of code: http://groups.google.com/group/comp.lang.php/browse_thread/thread/e02037a5c14e54c9/3288eeef436b64f7

Let me know if this works.

 

It's not exactly the same, but it might be useful to you as well: www.php.net/debug_backtrace

 

Try this:
<?php
$test= ' something ';
echo ' $test is '. $test;
?>
The difference is in ' and " sign
Same code, change the sign and see the output
<?php
$test= ' something ';
echo " $test is ". $test;
?>

First one will print the variable name, second will print it's value.

 

ah, I am actually looking *not* to use

echo '$s is ', $s, "\n";

but just p($s) and it will accomplish the task of printing out

$s is Hello World

it is possible in C and in Ruby... wonder if it is possible in PHP.

 

is it true that... what if $s is Hello World and $b is Hello World, then will it always print the right variable name? (or if $a is 0 and $i is 0)