util.string.match

Syntax

local ... = util.string.match(
    input,
    pattern,
    start_at = 1
)

Parameters

Type	Name	Description
`string`	input	String to search in
`string`	pattern	Lua pattern to match
`int`	start_at	Position to start searching from - negative counts from end

Returns

Type	Name	Description
`any` \| `nil`	...	Captured strings or `nil` if no match is found

Examples

Match and return an entire pattern

local result = util.string.match("hello 123", "%d+")

core.engine.print("info", result) -- '123'

Match with a single capture group

local num = util.string.match("Price: $25", "%$(%d+)")

core.engine.print("info", num) -- '25'

Extract multiple captures at once

local word1, word2 = util.string.match("hello world", "(%a+) (%a+)")

core.engine.print("info", word1, word2) -- 'hello  world'

Extract user and domain from an email

local user, domain = util.string.match("john@example.com", "(.+)@(.+)")

core.engine.print("info", user) -- 'john'
core.engine.print("info", domain) -- 'example.com'

Match starting from a specific position

local result = util.string.match("hello hello", "hello", 7)

core.engine.print("info", result) -- 'hello'

Extract a number from a string

local num = util.string.match("Temperature: 25°C", "%d+")

core.engine.print("info", num) -- '25'

Extract text from within quotes

local text = 'name="John Doe"'
local value = util.string.match(text, '"(.-)"')

core.engine.print("info", value) -- 'John Doe'

Parse URL into protocol, domain, and path

local url = "https://example.com/path"
local protocol, domain, path = util.string.match(url, "(.-)://([^/]+)(.+)")

core.engine.print("info", protocol) -- 'https'
core.engine.print("info", domain) -- 'example.com'
core.engine.print("info", path) -- '/path'

Return nil when no match is found

local result = util.string.match("hello", "%d+")

core.engine.print("info", result) -- nil

Extract a semantic version number

local version = util.string.match("v1.2.3", "v(%d+%.%d+%.%d+)")

core.engine.print("info", version) -- '1.2.3'

Match the first word in a string

local word = util.string.match("  hello world  ", "%a+")

core.engine.print("info", word) -- 'hello'

Extract a hexadecimal color code

local color = util.string.match("color: #FF5733", "#(%x+)")

core.engine.print("info", color) -- 'FF5733'

Validate and extract a username

local text = "user123"
local name = util.string.match(text, "^(%a+%d+)$")

if name then
    core.engine.print("info", "Valid username:", name)
end

Extract a key-value pair

local key, value = util.string.match("setting=enabled", "(.-)=(.*)")

core.engine.print("info", key, value) -- 'setting  enabled'

Capture the position after a match

local text = "hello world"
local pos = util.string.match(text, "world()")

core.engine.print("info", pos) -- 12

Syntax

Parameters

Returns

Examples

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