85 lines
1.6 KiB
Markdown
85 lines
1.6 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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videoUrl: 'https://scrimba.com/c/cNpM8AN'
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forumTopicId: 16802
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dashedName: concatenating-strings-with-plus-operator
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---
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# --description--
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In JavaScript, when the `+` operator is used with a `String` 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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**Example**
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```js
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'My name is Alan,' + ' I concatenate.'
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```
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**Note**
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Watch out for spaces. Concatenation does not add spaces between concatenated strings, so you'll need to add them yourself.
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Example:
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```js
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var ourStr = "I come first. " + "I come second.";
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// ourStr is "I come first. I come second."
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```
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# --instructions--
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Build `myStr` from the strings `"This is the start. "` and `"This is the end."` using the `+` operator.
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# --hints--
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`myStr` should have a value of `This is the start. This is the end.`
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```js
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assert(myStr === 'This is the start. This is the end.');
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```
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You should use the `+` operator to build `myStr`.
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```js
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assert(code.match(/(["']).*\1\s*\+\s*(["']).*\2/g));
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```
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`myStr` should be created using the `var` keyword.
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```js
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assert(/var\s+myStr/.test(code));
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```
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You should assign the result to the `myStr` variable.
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```js
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assert(/myStr\s*=/.test(code));
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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(){
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if(typeof myStr === 'string') {
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return 'myStr = "' + myStr + '"';
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} else {
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return 'myStr is not a string';
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}
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})();
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```
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## --seed-contents--
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```js
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var myStr; // Change this line
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```
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# --solutions--
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```js
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var myStr = "This is the start. " + "This is the end.";
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```
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