format(fmt: string[, ...]) -> string


Formats args according to specifications in fmt and returns the result as a string.

Supported arguments:

  • boolean

  • number

  • string

You may also specify pairs. First element must be a string and it works as a named argument.

format() is a global so it doesn’t need to be require()d.


format("{0}, {1}, {2}", 'a', 'b', 'c')
-- Result: "a, b, c"

format("{}, {}, {}", 'a', 'b', 'c')
-- Result: "a, b, c"

format("{2}, {1}, {0}", 'a', 'b', 'c')
-- Result: "c, b, a"

format("{0}{1}{0}", "abra", "cad") -- arguments' indices can be repeated
-- Result: "abracadabra"

format("{:.{}f}", 3.14, 1)
-- Result: "3.1"

format("Elapsed time: {s:.2f} seconds", {"s", 1.23})
-- Result: "Elapsed time: 1.23 seconds"