JS Practice — Built-in Objects

Function.length — default parameters not counted

📖 Usage Example

function fn(...args) {}
fn.length  // → 0 (rest params not counted)

Rest parameters are not included in Function.length.

fn.length — defaults excluded

Parameters with default values are not counted in fn.length. Only the parameters before the first default are counted.

Challenge: Verify that function h(a, b = 1) {} has h.length === 1.

💡 Hints (1)