This class simply holds a string with a native Javascript Expression, so objects | arrays to be encoded with Zend_Json can contain native Javascript Expressions.

Example: $foo = array( 'integer' =>9, 'string' =>'test string', 'function' => Zend_Json_Expr( 'function(){ window.alert("javascript function encoded by Zend_Json") }' ), );

Zend_Json::encode($foo, false, array('enableJsonExprFinder' => true)); // it will returns json encoded string: // {"integer":9,"string":"test string","function":function(){window.alert("javascript function encoded by Zend_Json")}}