WEBVTT

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Now REPL stands for Read Evaluation Print Loop, and it basically allows you to execute code in bite sized

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chunks, just like what we did with the Chrome Developer Tools Console inside Chrome.

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We were able to write a single line of code and then hit enter and it would run that line of code and

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then we could run another line of code etc..

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So by installing Node, we also installed the Node REPL, and to access it all we do is write the command

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node inside the command line and hit enter.

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And once you see that little angle bracket, then you know you're inside the REPL.

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So here we can write code directly.

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So for example, I could write console.log

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(“Hey there!”), and if I hit enter then it will execute it straight away.

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And we should be pretty familiar with this already, as it works pretty much the same as our Chrome Console.

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So we can also execute other bits of code, for example 3 + 5 equals 8, or “Angela “ +

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“Yu” will be my name, Angela Yu, as a string.

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And it's also got short cuts, like, for example, if we didn't feel like writing out the entirety of console.log

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we can write con, tab,

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and if one tab doesn't give you any results, you can tab again and that will give you all the possible

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commands that you can use

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at this point.

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So you can use console, constructor, continue.

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So we want console.

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So console, and then we can write dot and I tap twice,

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then I can see all of the different possibilities. Now

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sometimes, while you're working in the command line, one of the most difficult things can be figuring

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out how to exit the process that you're currently in.

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Now, in order to exit the REPL, you can either say .exit and hit enter, or you can simply hit Control

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C twice. And in a lot of cases in the future, when we're running servers, or when we’re starting processes, Control C

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will usually get out of any process that you're running at that time.

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And if you wanted to clear your console, you can simply just write clear, and it will delete all of the

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previous commands.

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Now that was a little brief intro into what you can do using the Node REPL.

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Now in the next lesson, we're going to look at how you can use some native node modules, so packages of

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code, that's been bundled into Node that we can use to make our lives easier and to perform some really

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simple functionality.

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So for all of that and more, I'll see you on the next lesson.