Lists

List commands for storing ordered sequences of elements.

Commands

Command	Syntax	Description
LPUSH	LPUSH key element [element ...]	Prepend elements
RPUSH	RPUSH key element [element ...]	Append elements
LPOP	LPOP key [count]	Pop from front
RPOP	RPOP key [count]	Pop from back
LLEN	LLEN key	Get list length
LRANGE	LRANGE key start stop	Get range of elements
LINDEX	LINDEX key index	Get element by index
LSET	LSET key index element	Set element at index
LTRIM	LTRIM key start stop	Trim list to range
LREM	LREM key count element	Remove elements by value
LINSERT	LINSERT key BEFORE|AFTER pivot element	Insert before/after element

Blocking Commands (Server Mode Only)

Command	Syntax	Description
BLPOP	BLPOP key [key ...] timeout	Blocking pop from front
BRPOP	BRPOP key [key ...] timeout	Blocking pop from back

Examples

Basic Operations

# Push elements
127.0.0.1:6379> RPUSH mylist "one" "two" "three"
(integer) 3
127.0.0.1:6379> LPUSH mylist "zero"
(integer) 4

# Get all elements
127.0.0.1:6379> LRANGE mylist 0 -1
1) "zero"
2) "one"
3) "two"
4) "three"

# Pop elements
127.0.0.1:6379> LPOP mylist
"zero"
127.0.0.1:6379> RPOP mylist
"three"

Index Operations

# Get by index (0-based)
127.0.0.1:6379> LINDEX mylist 0
"one"
127.0.0.1:6379> LINDEX mylist -1  # Last element
"two"

# Set by index
127.0.0.1:6379> LSET mylist 0 "first"
OK

Range Operations

# Get subset
127.0.0.1:6379> LRANGE mylist 0 1
1) "first"
2) "two"

# Trim list (keep only elements 0-2)
127.0.0.1:6379> LTRIM mylist 0 2
OK

Remove Elements

127.0.0.1:6379> RPUSH mylist "a" "b" "a" "c" "a"
(integer) 5

# Remove 2 occurrences of "a" from head
127.0.0.1:6379> LREM mylist 2 "a"
(integer) 2

# Remove all occurrences (count = 0)
127.0.0.1:6379> LREM mylist 0 "a"
(integer) 1

Insert Elements

127.0.0.1:6379> RPUSH mylist "Hello" "World"
(integer) 2
127.0.0.1:6379> LINSERT mylist BEFORE "World" "Beautiful"
(integer) 3
127.0.0.1:6379> LRANGE mylist 0 -1
1) "Hello"
2) "Beautiful"
3) "World"

Blocking Operations (Server Mode)

# Wait up to 5 seconds for an element
127.0.0.1:6379> BLPOP myqueue 5
# Returns nil after timeout, or element if pushed by another client

# In another terminal:
127.0.0.1:6379> RPUSH myqueue "message"

Library Mode (Rust)

use redlite::Db;

let db = Db::open("mydata.db")?;

// Push elements
db.rpush("mylist", &[b"one", b"two", b"three"])?;
db.lpush("mylist", &[b"zero"])?;

// Get range
let elements = db.lrange("mylist", 0, -1)?;  // Vec<Vec<u8>>

// Pop elements
let first = db.lpop("mylist", 1)?;  // Vec<Vec<u8>>
let last = db.rpop("mylist", 1)?;

// Get by index
let elem = db.lindex("mylist", 0)?;  // Option<Vec<u8>>

// List length
let len = db.llen("mylist")?;

// Remove elements
db.lrem("mylist", 2, b"a")?;

// Insert
db.linsert("mylist", "BEFORE", b"World", b"Beautiful")?;

Use Cases

Message Queues

# Producer
RPUSH tasks '{"task": "process_image", "id": 123}'

# Consumer (blocking)
BLPOP tasks 0  # Wait indefinitely

Recent Items

# Add to front, keep last 100
LPUSH recent:user:1 "viewed:product:456"
LTRIM recent:user:1 0 99

Logs

RPUSH log:app "2024-01-01 12:00:00 INFO: Started"
RPUSH log:app "2024-01-01 12:00:01 DEBUG: Processing"
LRANGE log:app -10 -1  # Last 10 entries