77 lines
2.2 KiB
Markdown
77 lines
2.2 KiB
Markdown
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---
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id: 56533eb9ac21ba0edf2244b7
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title: Concatenating Strings with Plus Operator
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challengeType: 1
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---
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## Description
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<section id='description'>
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In JavaScript, when the <code>+</code> operator is used with a <code>String</code> value, it is called the <dfn>concatenation</dfn> operator. You can build a new string out of other strings by <dfn>concatenating</dfn> them together.
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<strong>Example</strong>
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<blockquote>'My name is Alan,' + ' I concatenate.'</blockquote>
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<strong>Note</strong><br>Watch out for spaces. Concatenation does not add spaces between concatenated strings, so you'll need to add them yourself.
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</section>
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## Instructions
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<section id='instructions'>
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Build <code>myStr</code> from the strings <code>"This is the start. "</code> and <code>"This is the end."</code> using the <code>+</code> operator.
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</section>
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## Tests
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<section id='tests'>
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```yml
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- text: <code>myStr</code> should have a value of <code>This is the start. This is the end.</code>
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testString: 'assert(myStr === "This is the start. This is the end.", "<code>myStr</code> should have a value of <code>This is the start. This is the end.</code>");'
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- text: Use the <code>+</code> operator to build <code>myStr</code>
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testString: 'assert(code.match(/([""]).*([""])\s*\+\s*([""]).*([""])/g).length > 1, "Use the <code>+</code> operator to build <code>myStr</code>");'
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- text: <code>myStr</code> should be created using the <code>var</code> keyword.
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testString: 'assert(/var\s+myStr/.test(code), "<code>myStr</code> should be created using the <code>var</code> keyword.");'
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- text: Make sure to assign the result to the <code>myStr</code> variable.
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testString: 'assert(/myStr\s*=/.test(code), "Make sure to assign the result to the <code>myStr</code> variable.");'
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='js-seed'>
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```js
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// Example
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var ourStr = "I come first. " + "I come second.";
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// Only change code below this line
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var myStr;
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```
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</div>
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### After Test
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<div id='js-teardown'>
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```js
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console.info('after the test');
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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var ourStr = "I come first. " + "I come second.";
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var myStr = "This is the start. " + "This is the end.";
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```
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</section>
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