4d620dea1a
* chore(curriculum): update regex in use-braket-notation-* tests Update regex used in tests, so that tests are more forgiving and spaces tolerant. * Allow for spaces within brackets
75 lines
1.7 KiB
Markdown
75 lines
1.7 KiB
Markdown
---
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id: bd7123c9c549eddfaeb5bdef
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title: Use Bracket Notation to Find the First Character in a String
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/ca8JwhW'
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forumTopicId: 18341
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dashedName: use-bracket-notation-to-find-the-first-character-in-a-string
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---
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# --description--
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<dfn>Bracket notation</dfn> is a way to get a character at a specific index within a string.
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Most modern programming languages, like JavaScript, don't start counting at 1 like humans do. They start at 0. This is referred to as <dfn>Zero-based</dfn> indexing.
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For example, the character at index 0 in the word `Charles` is `C`. So if `const firstName = "Charles"`, you can get the value of the first letter of the string by using `firstName[0]`.
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Example:
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```js
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const firstName = "Charles";
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const firstLetter = firstName[0];
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```
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`firstLetter` would have a value of the string `C`.
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# --instructions--
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Use bracket notation to find the first character in the `lastName` variable and assign it to `firstLetterOfLastName`.
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**Hint:** Try looking at the example above if you get stuck.
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# --hints--
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The `firstLetterOfLastName` variable should have the value of `L`.
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```js
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assert(firstLetterOfLastName === 'L');
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```
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You should use bracket notation.
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```js
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assert(code.match(/firstLetterOfLastName\s*=\s*lastName\s*\[\s*\d\s*\]/));
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```
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# --seed--
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## --after-user-code--
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```js
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(function(v){return v;})(firstLetterOfLastName);
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```
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## --seed-contents--
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```js
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// Setup
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let firstLetterOfLastName = "";
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const lastName = "Lovelace";
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// Only change code below this line
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firstLetterOfLastName = lastName; // Change this line
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```
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# --solutions--
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```js
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let firstLetterOfLastName = "";
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const lastName = "Lovelace";
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// Only change code below this line
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firstLetterOfLastName = lastName[0];
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```
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