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JavaScript JavaScript Loops, Arrays and Objects Simplify Repetitive Tasks with Loops The Refactor Challenge

what is the point of var html = '';

var html = ''

2 Answers

Alexander Gyger
Alexander Gyger
14,237 Points

With

var html = '';

you define that (html) is a string(text)-variable. ('') contains a specific, but empty text. After this definition you can add other strings (+ 'other string') to it later.

If you don't define this (html) as a string-variable, just only the variable:

var html;

it will give you an ugly "undefined"-Error in the output, since the script will try to add a string to a variable which isn't defined.

Seth Roope
Seth Roope
6,471 Points

This is correct. You are just setting the type of the variable by defining it as an empty string.

It's declaring an empty string variable to be used later. You can write it with either single quotes or double quotes.

var html = '';
var html = "";

and then later you might set it to something like

html = 'string';

or

html = "string";

so it just a space so if i wrote prompt('Hello' + html +'Mom') It would say Hello Mom ?

Only if you put a space in the variable.

var html = '';

is not the same as

var html = ' ';