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1. Aral Balkan (aral@mastodon.ar.al)'s status on Thursday, 31-Aug-2023 18:25:55 JST Aral Balkan

   Ran into this basic JavaScript scope gotcha today.

   Just goes to show, you could be programming in a language for years and still get tripped up by some of the simplest issues.

   https://codeberg.org/aral/gists/src/branch/main/javascriptScope.md

   #JavaScript #scope #web #dev

   • Aral Balkan (aral@mastodon.ar.al)'s status on Thursday, 31-Aug-2023 18:33:22 JST Aral Balkan

     in reply to

     • Ekaitz Zárraga 👹

     @ekaitz_zarraga Yeah ;)

     “It looks like it’s going to work because we’re used to things being hoisted in JavaScript but that only goes for functions.”

   • Ekaitz Zárraga 👹 (ekaitz_zarraga@mastodon.social)'s status on Thursday, 31-Aug-2023 18:33:23 JST Ekaitz Zárraga 👹

     in reply to

     @aral If you want to learn more about it, it happens because `const` doesn't apply hoisting in the way you are expecting it to:
     https://developer.mozilla.org/en-US/docs/Glossary/Hoisting

   • Aral Balkan (aral@mastodon.ar.al)'s status on Thursday, 31-Aug-2023 18:34:21 JST Aral Balkan

     in reply to

     • Ekaitz Zárraga 👹

     @ekaitz_zarraga Although, thanks for the link, I’ll add it to the gist :)

   • Piggo :verified_horse: (piggo@piggo.space)'s status on Thursday, 31-Aug-2023 18:35:05 JST Piggo :verified_horse:

     in reply to
     @aral of course, if you used 'var' instead of 'const', it would work. No, it doesn't make sense
   • Aral Balkan (aral@mastodon.ar.al)'s status on Thursday, 31-Aug-2023 18:36:35 JST Aral Balkan

     in reply to

     • Piggo :verified_horse:
     • Ekaitz Zárraga 👹

     @ekaitz_zarraga @piggo Thanks, folks, updated the gist with your contributions:

     https://codeberg.org/aral/gists/src/branch/main/javascriptScope.md

   • Ekaitz Zárraga 👹 (ekaitz_zarraga@mastodon.social)'s status on Thursday, 31-Aug-2023 18:38:22 JST Ekaitz Zárraga 👹

     in reply to

     @aral it's not only for functions. It's way more complex than that.
     It's a lot of fun.

   • Aral Balkan (aral@mastodon.ar.al)'s status on Thursday, 31-Aug-2023 18:38:22 JST Aral Balkan

     in reply to

     • Ekaitz Zárraga 👹

     @ekaitz_zarraga Yay! :)

   • Jeroen Baert (jbaert@mastodon.social)'s status on Thursday, 31-Aug-2023 19:17:59 JST Jeroen Baert

     in reply to

     @aral Shouldn't even be able to call greet() in the first place! Undeclared!

     *strokes long beard*

   • Aral Balkan (aral@mastodon.ar.al)'s status on Thursday, 31-Aug-2023 19:17:59 JST Aral Balkan

     in reply to

     • Jeroen Baert

     @jbaert Yeah, hoisting is fun (when it works) :)

   • Jeroen Baert (jbaert@mastodon.social)'s status on Thursday, 31-Aug-2023 19:18:00 JST Jeroen Baert

     in reply to

     @aral Me, as a C developer, not blinking: "Well of course!"

   • Aral Balkan (aral@mastodon.ar.al)'s status on Thursday, 31-Aug-2023 19:18:52 JST Aral Balkan

     in reply to

     • Ekaitz Zárraga 👹

     @ekaitz_zarraga Yeah, teaching is the best way to learn ;)

   • Ekaitz Zárraga 👹 (ekaitz_zarraga@mastodon.social)'s status on Thursday, 31-Aug-2023 19:18:53 JST Ekaitz Zárraga 👹

     in reply to

     @aral btw I know this because I've been teaching JS... if I didn't I wouldn't know about this.
     These concepts are hard to find or learn about if you are just coding on JS.

   • David Hayes :prami: (drhayes@social.lol)'s status on Thursday, 31-Aug-2023 22:32:26 JST David Hayes :prami:

     in reply to

     @aral I'm sure you're sick of people popping in to explain this at you, so I won't do that.

     But I *will* say this has the coolest name of anything I know of in programming: it's the TEMPORAL DEAD ZONE!

     A touch of Star Trek in our JavaScript!

   • Aral Balkan (aral@mastodon.ar.al)'s status on Thursday, 31-Aug-2023 22:32:26 JST Aral Balkan

     in reply to

     • David Hayes :prami:

     @drhayes Ooh, I like that :)

   • Aral Balkan (aral@mastodon.ar.al)'s status on Thursday, 31-Aug-2023 22:38:13 JST Aral Balkan

     in reply to

     • David Hayes :prami:

     @drhayes Just updated the gist with a reference to your toot and the MDN explanation of Temporal Dead Zone :) Thanks again :)

     https://codeberg.org/aral/gists/src/branch/main/javascriptScope.md