The unexpected token "[ ]" was encountered while assigning a numerical value to an array

Hey everyone, I have a question that's been bothering me and I can't seem to find the answer anywhere.

I'm currently learning pure JavaScript and although I am familiar with several other programming languages, I keep running into an issue with array assignment in JS.

    var gear = []; // global assignment

    gear[0]=200; // this line is causing an error

    function bla(){

        gear[0] = 200;// even putting it in a function doesn't work
    }

// I keep getting an unexpected token "[" error. It's frustrating because even BASIC allows this.

After some research, I realized that my placement of the assignment may be incorrect. I've tried assigning globally and inside a function, but I still encounter errors.

So here are my questions regarding pure JS: Is it not possible to assign a numerical value to an array? Where should I place this assignment? If I'm doing this wrong (which seems likely), how can I make index 0 equal to a specific value? Do I need to use parentheses? My program was functioning perfectly until I tried adding arrays, now I'm stuck on this token error. (I could easily do this with console API, but I prefer a web-based solution)

Thank you all for your help!

javascriptarraysscope

Answer №1

After some investigation, I realized that none of my initial assumptions were correct. It turns out that the error was caused by a mistake when initializing a variable and then trying to assign it a value:

For example:

var gear = []; // Initializing the array - this is fine
gear[0] = 200; // Assigning a value - this is also fine, but....

var gear[0] = 200;// In the later part of the code, I found this line which led to the error.

In most programming languages, including JavaScript, re-declaring a variable using "var" is not allowed unless the original declaration does not exist. This behavior can be confusing as other languages like PHP and Pascal are more lenient in this regard.

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