PHP Decode

--TEST--
Test strtr() function : usage variations - regular & numeric strings for 'str' argument
--FILE--
<?php
/* Testing strtr() function by passing the
 *   combination of numeric & regular strings for 'str' argument and
 *   corresponding translation pair of chars for 'from', 'to' & 'replace_pairs' arguments
*/

echo "*** Testing strtr() : numeric & regular double quoted strings ***\n";
/* definitions of required input variables */
$count = 1;
$heredoc_str = <<<EOD
123
abc
1a2b3c
EOD;
//array of string inputs for $str
$str_arr = array(
  //double quoted strings
  "123",
  "abc",
  "1a2b3c",

  //single quoted strings
  '123',
  'abc',
  '1a2b3c',

  //heredoc string
  $heredoc_str
);
$from = "123abc";
$to = "abc123";
$replace_pairs = array("1" => "a", "a" => 1, "2b3c" => "b2c3", "b2c3" => "3c2b");

/* loop through to test strtr() with each element of $str_arr */
for($index = 0; $index < count($str_arr); $index++) {
  echo "-- Iteration $count --\n";

  $str = $str_arr[$index];  //getting the $str_arr element in $str variable

  //strtr() call in three args syntax form
  var_dump( strtr($str, $from, $to) );

  //strtr() call in two args syntax form
  var_dump( strtr($str, $replace_pairs) );

  $count++;
}
echo "*** Done ***";
?>
--EXPECT--
*** Testing strtr() : numeric & regular double quoted strings ***
-- Iteration 1 --
string(3) "abc"
string(3) "a23"
-- Iteration 2 --
string(3) "123"
string(3) "1bc"
-- Iteration 3 --
string(6) "a1b2c3"
string(6) "a1b2c3"
-- Iteration 4 --
string(3) "abc"
string(3) "a23"
-- Iteration 5 --
string(3) "123"
string(3) "1bc"
-- Iteration 6 --
string(6) "a1b2c3"
string(6) "a1b2c3"
-- Iteration 7 --
string(14) "abc
123
a1b2c3"
string(14) "a23
1bc
a1b2c3"
*** Done ***