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Specify Upper and Lower Number of Matches

curriculum/challenges/english/blocks/regular-expressions/587d7db9367417b2b2512ba5.md

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--description--

Recall that you use the plus sign + to look for one or more characters and the asterisk * to look for zero or more characters. These are convenient but sometimes you want to match a certain range of patterns.

You can specify the lower and upper number of patterns with <dfn>quantity specifiers</dfn>. Quantity specifiers are used with curly brackets ({ and }). You put two numbers between the curly brackets - for the lower and upper number of patterns.

For example, to match only the letter a appearing between 3 and 5 times in the string ah, your regex would be /a{3,5}h/.

js
let A4 = "aaaah";
let A2 = "aah";
let multipleA = /a{3,5}h/;
multipleA.test(A4);
multipleA.test(A2);

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

--instructions--

Change the regex ohRegex to match the entire phrase Oh no only when it has 3 to 6 letter h's.

--hints--

Your regex should use curly brackets.

js
assert(ohRegex.source.match(/{.*?}/).length > 0);

Your regex should not match the string Ohh no

js
ohRegex.lastIndex = 0;
assert(!ohRegex.test('Ohh no'));

Your regex should match the string Ohhh no

js
assert('Ohhh no'.match(ohRegex)[0].length === 7);

Your regex should match the string Ohhhh no

js
assert('Ohhhh no'.match(ohRegex)[0].length === 8);

Your regex should match the string Ohhhhh no

js
assert('Ohhhhh no'.match(ohRegex)[0].length === 9);

Your regex should match the string Ohhhhhh no

js
assert('Ohhhhhh no'.match(ohRegex)[0].length === 10);

Your regex should not match the string Ohhhhhhh no

js
ohRegex.lastIndex = 0;
assert(!ohRegex.test('Ohhhhhhh no'));

--seed--

--seed-contents--

js
let ohStr = "Ohhh no";
let ohRegex = /change/; // Change this line
let result = ohRegex.test(ohStr);

--solutions--

js
let ohStr = "Ohhh no";
let ohRegex = /Oh{3,6} no/; // Change this line
let result = ohRegex.test(ohStr);