Error: The function clickHandler has been referenced before it was declared or it has already been declared

Since I started using JSLint, I have encountered the common issues of "used before defined" and "is already defined." While I found solutions for some problems, I am currently stuck. Here is a snippet of my code:

var foo;   
foo = addEventListener("click", clickHandler, false);  
... 
function clickHandler() {...};

The code works as it is, but I receive the "used before defined" warning. If I include clickHandler in the "var" statement, it will be undefined when called, requiring me to rearrange my code and place the handler definition in the middle (reducing readability). Is there a way to use clickHandler and still define it after it's been used?

javascriptjslint

Answer №1

Consider restructuring your code in the following way:

var foo;   
foo = addEventListener("click", clickHandler, false);  
function clickHandler() {...};
...

Is there a method where I can utilize the clickHandler before defining it?

Absolutely! You can leave your code as is. It should function properly. JSLint may highlight potential issues or style discrepancies, but not everything flagged necessarily needs fixing.

For a more versatile linter, try using JSHint.

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