freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-and-data-structures/regular-expressions/match-beginning-string-patterns.md

id, title, challengeType, forumTopicId, dashedName

id	title	challengeType	forumTopicId	dashedName
587d7db7367417b2b2512b9d	Match Beginning String Patterns	1	301349	match-beginning-string-patterns

--description--

Prior challenges showed that regular expressions can be used to look for a number of matches. They are also used to search for patterns in specific positions in strings.

In an earlier challenge, you used the caret character (^) inside a character set to create a negated character set in the form [^thingsThatWillNotBeMatched]. Outside of a character set, the caret is used to search for patterns at the beginning of strings.

let firstString = "Ricky is first and can be found.";
let firstRegex = /^Ricky/;
firstRegex.test(firstString);
let notFirst = "You can't find Ricky now.";
firstRegex.test(notFirst);

The first test call would return true, while the second would return false.

--instructions--

Use the caret character in a regex to find Cal only in the beginning of the string rickyAndCal.

--hints--

Your regex should search for the string Cal with a capital letter.

assert(calRegex.source == '^Cal');

Your regex should not use any flags.

assert(calRegex.flags == '');

Your regex should match the string Cal at the beginning of the string.

calRegex.lastIndex = 0;
assert(calRegex.test('Cal and Ricky both like racing.'));

Your regex should not match the string Cal in the middle of a string.

calRegex.lastIndex = 0;
assert(!calRegex.test('Ricky and Cal both like racing.'));

--seed--

--seed-contents--

let rickyAndCal = "Cal and Ricky both like racing.";
let calRegex = /change/; // Change this line
let result = calRegex.test(rickyAndCal);

--solutions--

let rickyAndCal = "Cal and Ricky both like racing.";
let calRegex = /^Cal/; // Change this line
let result = calRegex.test(rickyAndCal);