Using Papa Parse why can I not reference the data that has been parsed?

Question

I am using Papa Parse to parse a csv file. In "complete" I try to assign the results, an array of objects, to a variable that I declared outside of my call to Papa Parse's parse function. The variable is fine inside of the function but undefined outside. I tried this also with a string and integer but the variable still is undefined outside of the function.

var data;
for (var i = 0, f; f = files[i]; i++) {
    if (f.type == 'application/csv' || f.type == 'application/vnd.ms-excel' || f.type == 'text/csv') {

        Papa.parse(f, {
            header: true,
            dynamicTyping: false,
            complete: function(results) {
                console.log("Completed parsing results", results);
                data = results.data.slice(0); //I tried other simple values here, such as "test"
                console.log("Data after assigned value.", data); //Here the data is correctly assigned to the variable

            }
        });

        console.log("Value of data outside function.", data); //Undefined??
    }
}

Answer 1

Parsing a file is a asynchronous, which is why your last console.log line doesn't have any results: it executes before parsing is complete. Your handling of the results must happen inside or after the complete callback.