Checking for the Existence of JavaScript Variables

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  • Опубликовано: 4 ноя 2024
  • When writing JavaScript there are going to be times when you want to use a variable or call a function, but you are not sure if it exists, then this is how you can handle these situations.
    Code from video: gist.github.co...

Комментарии • 30

  • @cholo2605
    @cholo2605 7 месяцев назад +1

    We miss you prof3!!

  • @St1diot
    @St1diot 6 месяцев назад +1

    I love you proffesor steve ❤❤

  • @shahinza
    @shahinza Год назад +1

    Hello Professor! I've truly missed your insightful videos. Your content has always been my go-to for simplifying complex topics. Hoping everything is going well for you. Looking forward to new uploads!

  • @chiggywiggy524
    @chiggywiggy524 6 месяцев назад

    You're the Bob Ross of programming ❤

  • @anthonydsouza8202
    @anthonydsouza8202 10 месяцев назад

    Hi professor. Great to know that you are writing a book. Surely, it's gonna be as awesome as your videos. Wishing you all the best.

  • @NurioonSoftware
    @NurioonSoftware 11 месяцев назад

    Professor. Your channel is Diamond 💎

  • @Felipekimst
    @Felipekimst Год назад +3

    Man, that wind out there got me scared lol

  • @Strasbourgeois
    @Strasbourgeois Год назад

    A script of type module creates it's own scope preventing var declarations from bubbling up to the global scope

  • @leonardchan2638
    @leonardchan2638 Год назад +1

    There's an edge case where, you just declare a variable (but don't assign a value to it) let varname; and typeof varname is actually 'undefined'. So you can't re-declare it. Not practically useful though...

  • @rationalindianguy
    @rationalindianguy 6 месяцев назад

    Hello sir.
    You are doing amazing... please upload React

  • @nro337
    @nro337 Год назад

    Great video!

  • @Fam-m4i
    @Fam-m4i Год назад +1

    Hi Steve, great content. I was wondering if you could make a video on Promise polyfill using es6 classes. It's commonly asked in interviews

    • @SteveGriffith-Prof3ssorSt3v3
      @SteveGriffith-Prof3ssorSt3v3  Год назад +2

      I have not heard of that being asked in many years. Node and all browsers all support Promises and have for years.

  • @RedaElMekkaoui-p9k
    @RedaElMekkaoui-p9k 6 месяцев назад

    Hey steve, I'm 15 year old and I only just started learning programming, I want to make it a career out of it, is starting at 15 ideal and how many years will it take me on average to achieve an intermediate or advanced level??

    • @SteveGriffith-Prof3ssorSt3v3
      @SteveGriffith-Prof3ssorSt3v3  6 месяцев назад +1

      In my program, I've taught 17 year olds and 60 year olds. Both of whom did great. The best time to start learning how to program is today.
      The time required to get to an intermediate level depends on the person and how much time is spent learning and practicing through building things. Could be a year, or could be five years. You also have to consider intermediate in which area. There are lots of areas to learn about in programming. You can be a beginner in a dozen and intermediate in a couple, and advanced in a couple others.

  • @shahinza
    @shahinza Год назад

    Thank you 🙏

  • @mayankshashi5557
    @mayankshashi5557 Год назад

    Hi sir, can you please make a video on how we can display image on webpage when we upload image data into indexdb in offline mode?

    • @SteveGriffith-Prof3ssorSt3v3
      @SteveGriffith-Prof3ssorSt3v3  Год назад

      This video explains how to work with files and data to display things on a webpage - ruclips.net/video/zq2xD-xuIG4/видео.html
      I do plan to make a video on how to save files with IndexedDB... not sure when but it is on my list.

  • @grenzhochspannungshindernis
    @grenzhochspannungshindernis Год назад

    Can you recommend any how-to-program books?

    • @SteveGriffith-Prof3ssorSt3v3
      @SteveGriffith-Prof3ssorSt3v3  Год назад +1

      There are thousands.
      It depends on what specifically you are trying to learn. What language? What framework? What technology?
      I recommend going to a book store and spend a couple hours flipping through books on the topic you want to learn. Pick a book whose author writes in a way that you understand. It doesn't matter what book or what you are learning. As long as you are learning, you are making progress. Programming is a life-long learning process. Just start.

  • @RalphGoddard-tt1xq
    @RalphGoddard-tt1xq Год назад

    If your not already, you might want to use a noise cancelling mike

    • @SteveGriffith-Prof3ssorSt3v3
      @SteveGriffith-Prof3ssorSt3v3  Год назад +1

      I do but there was a Tornado approaching while I was recording. Seriously.

    • @bmehder
      @bmehder Год назад

      @@SteveGriffith-Prof3ssorSt3v3 I was going to ask if you were recording the video during a tornado as a joke. Glad you made it through unharmed.