manipulating constant name as string

Hello I am trying to access the constant name as string and not the constant contents. For example, define('myconst', 'const text 1'); $myArray = array() myArray['myconst'] = "this is it" etc. $xmltext=""; foreach ($myArray as $key => $val) { echo "$key = $val\n\n"; $xmltext .= "$xmltext = $xmltext . "<$key> $val </$key>"; } Unfortunately, $key within the string concatenation is translated into the constant value. However, for the echo statement, then $key constant name is displayed. Is there a way to keep the constant name rather its value when manipulating it as a string? thanks, Daniel