--description--
Objects can be thought of as a key/value storage, like a dictionary. If you have tabular data, you can use an object to lookup values rather than a switch
statement or an if/else
chain. This is most useful when you know that your input data is limited to a certain range.
Here is an example of an article object:
const article = {
"title": "How to create objects in JavaScript",
"link": "https://www.freecodecamp.org/news/a-complete-guide-to-creating-objects-in-javascript-b0e2450655e8/",
"author": "Kaashan Hussain",
"language": "JavaScript",
"tags": "TECHNOLOGY",
"createdAt": "NOVEMBER 28, 2018"
};
const articleAuthor = article["author"];
const articleLink = article["link"];
const value = "title";
const valueLookup = article[value];
articleAuthor
is the string Kaashan Hussain
, articleLink
is the string https://www.freecodecamp.org/news/a-complete-guide-to-creating-objects-in-javascript-b0e2450655e8/
, and valueLookup
is the string How to create objects in JavaScript
.
--instructions--
Convert the switch statement into an object called lookup
. Use it to look up val
and assign the associated string to the result
variable.
--hints--
phoneticLookup("alpha")
should equal the string Adams
assert(phoneticLookup('alpha') === 'Adams');
phoneticLookup("bravo")
should equal the string Boston
assert(phoneticLookup('bravo') === 'Boston');
phoneticLookup("charlie")
should equal the string Chicago
assert(phoneticLookup('charlie') === 'Chicago');
phoneticLookup("delta")
should equal the string Denver
assert(phoneticLookup('delta') === 'Denver');
phoneticLookup("echo")
should equal the string Easy
assert(phoneticLookup('echo') === 'Easy');
phoneticLookup("foxtrot")
should equal the string Frank
assert(phoneticLookup('foxtrot') === 'Frank');
phoneticLookup("")
should equal undefined
assert(typeof phoneticLookup('') === 'undefined');
You should not modify the return
statement
assert(__helpers.removeJSComments(code).match(/return\sresult;/));
You should not use case
, switch
, or if
statements
assert(
!/case|switch|if/g.test(__helpers.removeJSComments(code).replace(/([/]{2}.*)|([/][*][^/*]*[*][/])/g, ''))
);
--seed--
--seed-contents--
// Setup
function phoneticLookup(val) {
let result = "";
// Only change code below this line
switch(val) {
case "alpha":
result = "Adams";
break;
case "bravo":
result = "Boston";
break;
case "charlie":
result = "Chicago";
break;
case "delta":
result = "Denver";
break;
case "echo":
result = "Easy";
break;
case "foxtrot":
result = "Frank";
}
// Only change code above this line
return result;
}
phoneticLookup("charlie");
--solutions--
function phoneticLookup(val) {
let result = "";
const lookup = {
alpha: "Adams",
bravo: "Boston",
charlie: "Chicago",
delta: "Denver",
echo: "Easy",
foxtrot: "Frank"
};
result = lookup[val];
return result;
}