Parsing error: cannot read properties of undefined (reading ‘map’)

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The error “parsing error: cannot read properties of undefined (reading ‘map’)” occurs when trying to access the map method of an undefined variable or property. This error typically happens when you are trying to loop over the elements of an array or perform operations on an object that is undefined.

To illustrate this with an example, let’s assume you have the following JavaScript code: 

    
      let arr;
      arr.map(item => {
        console.log(item);
      });

In this code, the variable “arr” is not defined or assigned any value. When trying to call the map method on an undefined variable, a parsing error will occur. To fix this error, you need to make sure that the variable “arr” is properly initialized with an array or any iterable object before using the map method.

Here’s an updated example that prevents the parsing error: 

    
      let arr = [1, 2, 3];
      arr.map(item => {
        console.log(item);
      });

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