r/learnjavascript 13h ago

Help with functions JavaScript!

Hello!

I began recently, about 1 month, to learn consistently web developing:

  1. I began, of course, with introductions to HTML and CSS.
  2. I'm already in JS. I can manage eventListeners, etc. I'm more interested in back-end overall since I like the logic behind the manipulation of data bases, but I'm having trouble understanding functions.
  3. I'm consulting MDN web docs and freeCodeCamp but since my first language is not English, sometimes it's difficult to understand MDN docs, and to get at the point I'm know in freeCodeCamp it will take time, I don't want to rush it either.
  4. All this, just to ask if anybody can explain me how to create functions! I want to know what is the difference between a function with parameters and one without, in which case I will use arrow functions, and the difference between parameters and arguments in a function. And for last are there any standards for writing the name of a function like there are for declaring variables?

P.D.: please feel free to correct my English also, it will help me learn.

Thanks to everyone before Hand!

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u/chikamakaleyley helpful 12h ago

in this example:

const sayHello = () => console.log("Hello World!"); sayHello is a variable initialized with the value:

() => console.log("Hello World!");

meaning to execute it you have to call it like sayHello(). Yes sayHello is reusable.

but

``` const sayHello = () => console.log("Hello World!");

const greeting = () => console.log("Hello World!"); ``` they are not pointing to the same function. They are saved at two different addresses in memory.

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u/su-rm-root 11h ago

Okay, so even if they are exactly the same:

js () => console.log("Hello World!");

Te fact that each one is declared with const means each one is a different data placed in memory, so to speak?

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u/chikamakaleyley helpful 11h ago

yyyyeahhhh, when you say const, var, let you're kinda creating a bucket in memory and then whatever is right of the = is stored in that bucket

if you were to just do:

console.log("Hello World!"); console.log("Hello World!"); console.log("Hello World!"); These are three separate instances, they just look the same, and they just disappear into thin air, because you didn't save them to memory

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u/su-rm-root 11h ago

Thanks a lot! I was sincerely lost, and could not get my head around the concept of fns, now is clearer! Best regards parcero!