freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/understanding-case-sensitivity-in-variables.english.md

id, title, challengeType, videoUrl, forumTopicId

id	title	challengeType	videoUrl	forumTopicId
56533eb9ac21ba0edf2244ab	Understanding Case Sensitivity in Variables	1	https://scrimba.com/c/cd6GDcD	18334

Description

In JavaScript all variables and function names are case sensitive. This means that capitalization matters. MYVAR is not the same as MyVar nor myvar. It is possible to have multiple distinct variables with the same name but different casing. It is strongly recommended that for the sake of clarity, you do not use this language feature.

Best Practice

Write variable names in JavaScript in camelCase. In camelCase, multi-word variable names have the first word in lowercase and the first letter of each subsequent word is capitalized. Examples:

var someVariable;
var anotherVariableName;
var thisVariableNameIsSoLong;

Instructions

Modify the existing declarations and assignments so their names use camelCase.
Do not create any new variables.

Tests

tests:
  - text: <code>studlyCapVar</code> should be defined and have a value of <code>10</code>.
    testString: assert(typeof studlyCapVar !== 'undefined' && studlyCapVar === 10);
  - text: <code>properCamelCase</code> should be defined and have a value of <code>"A String"</code>.
    testString: assert(typeof properCamelCase !== 'undefined' && properCamelCase === "A String");
  - text: <code>titleCaseOver</code> should be defined and have a value of <code>9000</code>.
    testString: assert(typeof titleCaseOver !== 'undefined' && titleCaseOver === 9000);
  - text: <code>studlyCapVar</code> should use camelCase in both declaration and assignment sections.
    testString: assert(code.match(/studlyCapVar/g).length === 2);
  - text: <code>properCamelCase</code> should use camelCase in both declaration and assignment sections.
    testString: assert(code.match(/properCamelCase/g).length === 2);
  - text: <code>titleCaseOver</code> should use camelCase in both declaration and assignment sections.
    testString: assert(code.match(/titleCaseOver/g).length === 2);

Challenge Seed

// Variable declarations
var StUdLyCapVaR;
var properCamelCase;
var TitleCaseOver;

// Variable assignments
STUDLYCAPVAR = 10;
PRoperCAmelCAse = "A String";
tITLEcASEoVER = 9000;

Solution

var studlyCapVar;
var properCamelCase;
var titleCaseOver;

studlyCapVar = 10;
properCamelCase = "A String";
titleCaseOver = 9000;