April 2018
Beginner
536 pages
13h 21m
English
Trailing commas are the commas that are used after the last argument of a function. Using a comma after the last parameter of a function can be useful because it is very common for programmers to forget to add a comma when they modify an existing function by adding additional parameters.
For example, the following function only takes one parameter and doesn't use trailing commas:
function greetWithoutTralingCommas(
name: string
): string {
return `Hi! ${name}`;
}
After some time, we might be required to add a parameter to the preceding function. A common mistake is to declare the new parameter and forget to add a comma after the first parameter:
function updatedGreetWithoutTralingCommas( name: string ...