Description:
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Hi,
I am having one issues with json_encode function.  Let me explain briefly.

I want the json represented string from PHP Array. When I pass the array with not actually given 'key' value. json_encode return the encoded string as array. 
But after giving the array with associative array it is forcefully generated encoded as an object.

In short :
I can forcefully get the output of json_encode as an Object (using JSON_FORCE_OBJECT as 2nd Argument))
But can not forcefully get the output of json_encode as an Array (!!!?)

I really need josn_encode as an array in my functionality no matter key is given or not. Like added the JSON_FORCE_OBJECT there must be something for array.
ignore keys should be pass in optional argument.
Please do not say this is actual behavior of json. I need this solution in anyhow. 

Test script:
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<?php


/*I am giving array with no keys or numeric start with 0,2,3,4....with break sequence*/
$array = array("0" => "value1", "1" => "value2", "2" => "value3", "3" => "value4");
echo "Array output as array: ", json_encode($array);


echo "<br />";
/*I am giving array with no keys or numeric start with 0,2,3,4....with break sequence*/
$array = array("0" => "value1", "3" => "value2", "3" => "value3", "6" => "value4");
echo "Array output should be array: ", json_encode($array); // Need output as an Array here shows as an Object forcefully



Expected result:
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//Expected result:
Array output as array : ["value1","value2","value3","value4"]
Array output should be array: ["value1","value2","value3","value4"]

Actual result:
--------------
//Actual result:
Array output as array: ["value1","value2","value3","value4"]
Array output should be array: {"0":"value1","3":"value3","6":"value4"}