* fix: move "Explore Differences Between..." to basic JS, update seed and tests * fix: resequence "Declare String Variables" * fix: move "Declare a Read-Only Variable..." to basic JS, update seed and tests * fix: revert changes to non-English "Explore Differences Between..." test text * fix: revert test strings, solutions, and seeds for non-English challenges * fix: update "Declare String Variables" description * fix: sync quotation marks in description and seed * fix: modify note in "Declare a Read-Only..." challenge * fix: update operator and compound assignment challenges * fix: update string challenges * fix: update array and array method challenges * fix: update function and scope challenges, resequence slightly * fix: "Word Blanks" solution * fix: add spacing to seed * fix: concatenating += challenge spacing * fix: appending variables to strings spacing * fix: find the length of a string spacing * fix: removed instances of removedFromMyArray = 0 * fix: switch challenges * fix: function argument and param spacing * fix: update counting cards, object challenges, and record collection * fix: finish rest of Basic JS section * fix: introducing else statements solution * fix: update spacing and wording * fix: update wording for const challenge * fix: update functional programming challenges * fix: intermediate algorithms and cert challenges * fix: revert some spacing and remove comments for fp challenge solutions * feat: add notes with links to moved let and const challenges in first two es6 challenges * fix: update es6 intro text * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/concatenating-strings-with-the-plus-equals-operator.md Co-authored-by: Shaun Hamilton <shauhami020@gmail.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/finding-a-remainder-in-javascript.md Co-authored-by: Shaun Hamilton <shauhami020@gmail.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/global-scope-and-functions.md Co-authored-by: Shaun Hamilton <shauhami020@gmail.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/iterate-through-an-array-with-a-for-loop.md Co-authored-by: Shaun Hamilton <shauhami020@gmail.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/iterate-through-an-array-with-a-for-loop.md Co-authored-by: Shaun Hamilton <shauhami020@gmail.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/functional-programming/implement-map-on-a-prototype.md Co-authored-by: Shaun Hamilton <shauhami020@gmail.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/declare-a-read-only-variable-with-the-const-keyword.md Co-authored-by: Shaun Hamilton <shauhami020@gmail.com> * fix: concatenating strings with plus operator seed * fix: add comments back to Declare a Read-Only Variable... seed * feat: add es6 to basic javascript redirect tests for let and const challenges * fix: revert "Concatenating Strings with Plus Operator" seed * fix: move test file to cypress/integration/learn/redirects, separate redirect tests Co-authored-by: Shaun Hamilton <shauhami020@gmail.com>
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\[.*?\]/));
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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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