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Understand String Immutability

curriculum/challenges/english/blocks/basic-javascript/56533eb9ac21ba0edf2244ba.md

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--description--

In JavaScript, String values are <dfn>immutable</dfn>, which means that they cannot be altered once created.

For example, the following code will produce an error because the letter B in the string Bob cannot be changed to the letter J:

js
let myStr = "Bob";
myStr[0] = "J";

Note that this does not mean that myStr could not be re-assigned. The only way to change myStr would be to assign it with a new value, like this:

js
let myStr = "Bob";
myStr = "Job";

--instructions--

Correct the assignment to myStr so it contains the string value of Hello World using the approach shown in the example above.

--hints--

myStr should have a value of the string Hello World.

js
assert(myStr === 'Hello World');

You should not change the code above the specified comment.

js
assert(/myStr = "Jello World"/.test(__helpers.removeJSComments(code)));

--seed--

--seed-contents--

js
// Setup
let myStr = "Jello World";

// Only change code below this line
myStr[0] = "H"; // Change this line
// Only change code above this line

--solutions--

js
let myStr = "Jello World";
myStr = "Hello World";