9. Working with the REPL vs Using Files.srt

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Now before we finally dive into the javascript refresher or optionally in case you skip that, into the

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nodejs basics,

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let me dive into two different ways of executing your node code. One way of executing it which I briefly

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mentioned earlier in this module is the repl. Repl stands for read, reading user input, eval, evaluating

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user input, print, outputting a result and l, loop for returning and waiting for new input and the repl

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is what you use

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if you just type node into your terminal. Here I am in the terminal or on Windows this would be your command

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prompt and there if you just type node with node installed, you are now in the repl which you can identify

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by the fact that you now don't have that full path of your computer name at the beginning but just that

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greater than sign

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and there you can execute node commands like console log, two plus two or also writing, interacting with

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files.

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You can import the file system there just as we did it previously in our file and then we can use that

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to write a file synchronously and so on,

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so that will all work here

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and this is of course an environment where we don't store our code in files

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but we write our node application with every line.

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The lines don't work independent from each other,

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so I can now use the file system package for example

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now that I imported it one line earlier but once I quit out of this process with control c, I'm done.

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This is not saved anywhere,

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this is not a file I can execute again and this therefore is a great playground.

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The alternative to running codes is that you execute files as we did it before and as we will basically

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do it for the rest of the course,

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this is the alternative to using the repl. When you execute files,

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the advantage of course is and that is why we use it for real apps, that we write our code in advance

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and we can always execute it and when we build a real app, we want to save our code of course in files

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which we can then deploy in the end which we could share with other developers and where we can also pause

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our work and pick up later

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and where we never lose the code we write. But the repl is a great playground because we can use that to run some

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commands, to try out certain things because we execute code as we write it and therefore these are the

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two ways of running your node code,

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obviously we'll go with the store code in files approach in this course

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but whenever I say repl, I'm referring to this direct input way which I can recommend for trying out

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some features but not for writing real applications,

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that is not what you would do.

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I just wanted to get these two ways out of the way,

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we'll focus on the left one here and with that, let's dive into writing some code with the next modules.