1. Area of visibility
Well, what’s the best way to avoid global variables? The answer is straightforward; you’d need to enclose your module in a defined function, for which there is a well-known approach — the use of “Immediate Function.”
2. Data structures
But if you need to store a sequential data set not by keys, then use arrays, since the speed of sequential enumeration of elements is much higher in it.
The effect of raising a variable (hoisting) is one of the most unobvious feature-set of the language. Wherever you define a variable inside a function, even before return, it will be defined literally as if you did it at the very starting point of the function.
First of all, it will have an undefined meaning, and then the meaning will be assigned to it in the code. Thus, an error caused by the effect of raising a variable may occur in this case. There is a practice that helps to avoid such problems—to define variables at the start of the function so that the effect of raising them becomes obvious.
5. Prototype and inheritance model
An empty object is always at the end of the prototype chain. It indicates the end of the search.
6. The insidious link “this”
There is a common approach to solving this problem. This is storing the meaning this into a variable and ==> using this variable in callback through closure.
7. Uncaught mistake
A similar error appears when trying to call a meaning as a function when the meaning is not a function.
To eliminate it, you should make sure that the function name is right. The line number always shows the correct place.
8. Uncaught range mistake
The error is usually connected with an incorrect program logic, which leads to an endless call to the recursive function.
To correct a mistake, it is necessary to verify recursive functions for errors that can force them to make recursive calls forever.
9. Unexpected token
It is usually caused by missing curly, round, or square brackets. In some cases, the line number does not indicate the correct location, which makes it difficult to correct the error.
10. Invalid state mistake
This suggests that the code called a function that could not be called in the current state. It is usually associated with XMLHttpRequest when trying to call functions on it until it is ready.
You should look at the code in the line indicating the error, and make sure that it is called at the right time or adds the necessary calls before that (as with xhr.open).
Other Notable Errors
Some other notable mistakes/errors that can easily be corrected by researching and being mindful of them are:
- Wrongly using the comparison operator of the “IF” Statement.
- Wrongly using named object indexes as arrays in your codings.
- Placing or using the “UNDEFINED” and “NULL” keywords wrongly.
- Frequently missing parentheses or leaving the brackets unmatched.
- Leaving out important references, the closing semicolon, and quotes.
- Wrongly Using the “return statement” and
- Constantly allowing memory leaks by leaving dangling references to disused objects.
Wrapping it UP: