Update RPOP.md

docs/src/content/docs/commands/RPOP.md

@@ -1,21 +1,22 @@
 ---
 title: RPOP
-description: The `RPOP` command in DiceDB removes and returns the last element of a list. It is commonly used for processing elements in Last-In-First-Out (LIFO) order.
+description: The `RPOP` command in DiceDB removes and returns elements from the end of a list. When provided with the optional `count` argument, the reply will consist of up to `count` elements, depending on the list's length. It is commonly used for processing elements in Last-In-First-Out (LIFO) order.
 ---
 
-The `RPOP` command in DiceDB is used to remove and return the last element of a list. This command is useful when processing elements in a Last-In-First-Out (LIFO) order.
+The `RPOP` command in DiceDB is used to remove and return elements from the end of a list. By default, it removes and returns a single element. When provided with the optional `count` argument, the reply will consist of up to `count` elements, depending on the list's length. This command is useful for processing elements in a Last-In-First-Out (LIFO) order.
 
 ## Syntax
 
 ```bash
-RPOP key
+RPOP key [count]
 ```
 
 ## Parameters
 
 | Parameter | Description                                                      | Type   | Required |
 | --------- | ---------------------------------------------------------------- | ------ | -------- |
 | `key`     | The key of the list from which the last element will be removed. | String | Yes      |
+| `count`   | The count of elemments to be removed.                            | Number | No       |
 
 ## Return values
 
@@ -24,14 +25,32 @@ RPOP key
 | The command is successful    | `String` The value of the last element in the list |
 | The key does not exist       | `nil`                                              |
 | The key is of the wrong type | error                                              |
+| The count is invalid         | error     |
+
+
+#### Behavior:
+
+1. **Key Existence and Type**:
+   - If the key does not exist, the command treats it as an empty list and returns `nil`.
+   - If the key exists but is not associated with a list, a `WRONGTYPE` error is returned.
+   - If more than one key is provided, an error is returned.
+
+2. **Without `count` Parameter**:
+   - If the list has elements and the optional `count` parameter is not provided, the last element of the list is removed and returned.
+
+3. **With `count` Parameter**:
+   - If the `count` parameter is provided:
+     - If the list has elements, up to `count` elements are removed from the end of the list and returned in order (from the last element to the earliest removed).
+     - If `count` is greater than the number of elements in the list, all elements are removed and returned.
+     - If `count` is less than 0, the following error is returned:
+       ```bash
+       (error) ERR value is not an integer or out of range
+       ```
+
+4. **Empty List**:
+   - If the list is empty, the command returns `nil`.
 
-## Behaviour
 
-- When the `RPOP` command is executed, DiceDB checks if the key exists and is associated with a list.
-- If the list has elements, the last element is removed and returned.
-- If the key does not exist, the command treats it as an empty list and returns `nil`.
-- If the key exists but is not associated with a list, a `WRONGTYPE` error is returned.
-- If more than one key is passed, an error is returned.
 
 ## Errors
 
@@ -42,17 +61,22 @@ RPOP key
 
 2. `Wrong number of arguments`
 
-   - Error Message: `(error) ERR wrong number of arguments for 'lpop' command`
+   - Error Message: `(error) ERR wrong number of arguments for 'rpop' command`
    - Occurs if command is executed without any arguments or with 2 or more arguments
 
+ 3. `Invalid Count`
+
+   - Error Message: `(error) ERR value is not an integer or out of range`
+   - Cause: Occurs if the count parameter is less than 0.    
+
 ## Example Usage
 
 ### Basic Usage
 
 ```bash
-127.0.0.1:7379> LPUSH mylist "one" "two" "three"
+LPUSH mylist "one" "two" "three"
 (integer) 3
-127.0.0.1:7379> RPOP mylist
+RPOP mylist
 "one"
 ```
 
@@ -61,7 +85,7 @@ RPOP key
 Returns `(nil)` if the provided key is non-existent
 
 ```bash
-127.0.0.1:7379> RPOP emptylist
+RPOP emptylist
 (nil)
 ```
 
@@ -72,7 +96,7 @@ Trying to `LPOP` a key `mystring` which is holding wrong data type `string`.
 ```bash
 SET mystring "hello"
 OK
-LPOP mystring
+RPOP mystring
 (error) WRONGTYPE Operation against a key holding the wrong kind of value
 ```
 
@@ -82,13 +106,30 @@ Passing more than one key will result in an error:
 
 ```bash
 RPOP mylist secondlist
-(error) ERR wrong number of arguments for 'lpop' command
+(error) ERR wrong number of arguments for 'rpop' command
 ```
 
+### Invalid Count Parameter
+
+Passing a negative value for count will result in an error:
+
+```bash
+RPOP mylist -1
+(error) ERR value is not an integer or out of range
+```
+
+Passing a non integer value as the count paramater will result in an error:
+
+```bash
+RPOP mylist secondlist
+(error) ERR value is not an integer or a float
+```
+
+
 ## Best Practices
 
 - `Check Key Type`: Before using `RPOP`, ensure that the key is associated with a list to avoid errors.
 - `Handle Non-Existent Keys`: Be prepared to handle the case where the key does not exist, as `RPOP` will return `nil` in such scenarios.
 - `Use in Conjunction with Other List Commands`: The `RPOP` command is often used alongside other list commands like [`RPUSH`](/commands/rpush), [`LPUSH`](/commands/lpush), [`LLEN`](/commands/llen), and [`LPOP`](/commands/lpop) to manage and process lists effectively.
 
-By understanding the `RPOP` command, you can effectively manage lists in DiceDB, ensuring that you can retrieve and process elements in a LIFO order.
+By understanding the `RPOP` command, you can effectively manage lists in DiceDB, ensuring that you can retrieve and process elements in a LIFO order.