Pops a value from the tail of a list, and pushes it to the front of another list. Also return this value.
从源LIST的最后弹出一个元素，并且把这个元素从目标LIST的顶部（左侧）压入目标LIST。
Parameters
Key: srckey
Key: dstkey
Return value
STRING The element that was moved in case of success, FALSE in case of failure.
Example
$redis->delete('x', 'y');
$redis->lPush('x', 'abc');
$redis->lPush('x', 'def');
$redis->lPush('y', '123');
$redis->lPush('y', '456');
// move the last of x to the front of y.
var_dump($redis->rpoplpush('x', 'y'));
var_dump($redis->lRange('x', 0, -1));
var_dump($redis->lRange('y', 0, -1));
Output:
string(3) "abc"
array(1) {
[0]=>
string(3) "def"
}
array(3) {
[0]=>
string(3) "abc"
[1]=>
string(3) "456"
[2]=>
string(3) "123"
}