Functions with variadic parameters — JavaScript fundamentals

Some functions have the interesting feature of accepting an indefinite number of parameters. And we're not talking about default values. Check out this example:

Math.max(1, 10, 3); // 10

The function Math.max() finds the maximum value among the passed parameters. How many parameters do you think it expects? This function's documentation shows something interesting:

  Math.max([value1[, value2[, ...]]])

The way it is written means this function accepts any number of parameters (even none). The optional parameters are specified by square brackets [ ], and so are the optional parameters with default values. The ability to pass any number of parameters is encoded with [, ...].

  Math.max(1, -3, 2, 3, 2); // 3